Tutorials/Mining

In the world of Minecraft, mining is a Player's best friend. But one must not be a fool while mining! Below are some great tips provided by the community.

The fastest way to reach bedrock (Though this does not yield very much ore and, can be very, very unsafe because of the risk of falling into a underground space or a lava pool.) is to dig straight down to bedrock and then pour water in the tunnel to easily swim up and down the shaft. Make air pockets up the shaft at intervals to avoid drowning.

Where should I mine?
Due to being the safest layer to mine at which also possesses all ores in reasonable quantities (especially diamond), Y-coordinate 12 is probably the best area in which to start mining. To find this, either press F3 while digging, find a lava pool, and stand on a block even with the top of the lava (not the actual lava!), or dig down to bedrock, find and stand on the uppermost layer of bedrock, then climb up 6 blocks. Once you have located the y=12 layer, you can begin mining, using one of the techniques listed below.

(note: lava lakes do exist at higher altitudes, and every once in a while a water lake will overwrite lava lower down, so bear in mind that not all lava lakes may be at the right level)

This chart shows the common range of ores, with the best layer noted on the right:

Starting Your Mine
Find a safe place to mine, then start it. Remember, when mining, always bring materials and food. Make sure that if you do mine, bring ladders so if you fall you will be able to get back up. Place random furnaces in the hallways in your mine so you can cook food if you didn't cook it already. With the food, make sure you have plenty. Make sure to bring a crafting table just in case you need to make an extra pickaxe. Lava is dangerous, so remember to bring a water bucket when mining. Of course, remember to bring torches for lighting. Always be prepared.

Quick Transport
A very sensible precaution for most mines would be to have an efficient transport system to transport goods out of harm's way, such as a railway. Making a rail system in your mine, then placing Minecarts with Chests on it with Powered Minecarts to push them (or Powered Rails if you can get them; they are more efficient) from station to station. Put all the things you find in them, then send them on their way out of the way of Lava. Be careful though; lava can burn the tracks, so make sure you put a barrier or enclose your rail system with stone, or similar material.

Cave Mining
Also known as Cave Hunting, Caving or Spelunking, Cave Mining is simply the practice of exploring caves and extracting the ores found there. Ore veins are often found exposed along the walls, floors and ceilings of caves; this is especially true after update 1.2, when the incidence of ores in and near caves was increased (see Version History). Exploring a large cave system almost always results in finding large quantities of ore. Cave mining has a high return on investment, yielding more ore per time spent and requiring fewer tools (less pickaxe and shovel durability is lost mining stone, dirt, and gravel) than other approaches.

On the other hand, cave mining is highly dangerous. Unexplored caves are dark and tend to contain many mobs; a sword, a bow and armor are practical necessities. The player should carry a large supply of torches to light up the cave and prevent extra mob spawns. Large cave systems can become confusing and special attention must be paid to navigation lest one quickly get lost. Moving through a cave too quickly makes it easy to miss unlit passages above or beside you, and carries the danger of stepping into an open shaft or falling into a lava pool. Portions of caves at level 11 and below are generally filled with lava. Because of these factors, players usually explore and light a cave first, then extract ores on the way back out, increasing the total time required and cutting down on mining efficiency.

The Cavern article contains tips on navigating large cave systems.

It is a good idea to carry a bucket of water. Caves often contain random lava flows, and cave areas below level 10 are filled with large lava pools. A bucket of water serves as both a fire extinguisher, if you fall in; and as a way to form obsidian surfaces over lava pools (pour water onto a solid block adjacent to a lava pool; do not stand between that spot and the lava). Another method is to go to options and change the difficulty to "Peaceful" this will prevent mobs from spawning. However, you could still die from lava, so don't forget that water bucket!

Cave Mining Checklist
1. A pickaxe. If it is your first mining trip, mine some cobblestone and make a stone pickaxe. If you are further along in the game, and expect to mine for a while, bring two iron pickaxes and at least one stone pickaxe. Once you have reached diamonds, if you have an efficient style of mine at a depth where diamonds are found, use a diamond pickaxe as it degrades slowly and is the only tool capable of mining obsidian. One usually uncovers enough diamonds to make several replacements for when it does break. If you prefer to save valuable materials, take a few stone pickaxes for mining stone and one iron pickaxe only for mining ores.

2. A Shovel. Having at least one iron shovel can get through cumbersome patches of dirt and gravel quickly without using your hands. Just one or two stone shovels also works if you want to use your iron for other things.

3. Torches. At least a full stack is recommended, and more is always better. Lighting the area around you can help you know which areas you have explored and not get lost, keep monster spawns down to a minimum, and find hidden ores in the shadows.

4. Wood. If you run out of tools or torches, you can make a crafting table and sticks to replenish your supplies of pickaxes, shovels, and torches (you can get more coal for them from mining).

5. A Water Bucket. This will be useful in saving your life and your items just in case you need to extinguish yourself if you catch on fire, if you come across a lava lake or pool you want to cross you can also use it to turn the lava into obsidian.

6. An empty bucket. An empty bucket is useful for collecting lava to use as fuel in a furnace, or to kill monsters with style. You can also use it to pick up more water if you lose your water bucket. Keep in mind that if it is used as fuel, the bucket is consumed as well as the lava.

7. Food. Prolonged visits in mines will wear away your hunger bar. Bringing food will allow you to spend more time your cave system and will also allow you to keep your hunger bar full so you automatically recover health when attacked by mobs.

8. Weapons: Any type of sword (preferably stone or better), a bow and plenty of arrows. These will help you defend yourself against monsters.

9. Armor. It will protect you from many hazards you can encounter when mining, from monsters to lava to steep drops.

10. Potion of fire resistance. Drink it when you are working near lava or fire - for example, when you are trying to get a resource located over an underground lava lake, or you need to dig straight down. The potion protects you from fire damage and even allows you to swim in lava unharmed. Ingredients needed for this potion are relatively rare, but it's quite easy to farm them once you locate their source. If you don't have potions yet, then carry a full bucket of water for the same reason.

11. Sticks, crafting table and a furnace to quickly make a new pickaxe/shovel/sword and to smelt your new iron ore with coal in case your pickaxe etc. breaks.

12. Chests. They are invaluable when exploring lava caves since you can store your items in case you die, you can die without a chest with a whole stack of iron and half a stack of gold (and they get burnt up) along with all of your food and weapons, or you can drop a chest and a workbench in a space and lose only your pickaxe and a few coal, torches and stone

13. (Optional) Redstone Torches and Redstone Dust. These can easily be used for marking routes, especially if you have extra redstone or have no use for it due to not needing to build an enormous computer that has a seven-segment display.

14. (Optional) Signs. These are also useful to mark your way outside a cavern by typing in them the right way outside. For example: EXIT --> or STORAGE ROOM -->

15: (Optional) Either Seeds or Melon Seeds. These are useful for starting a basic farm, along with a hoe and some dirt, for some emergency food if you run out.

Drifting
Caves often contain many dead-end passages and shafts. Many of these dead ends are actually thin barriers that, if removed, reveal continuing passages, sometimes into entire adjacent cave systems. Drifting is simply searching for adjacent caves by digging beyond apparent dead ends. Note that this increases the risk of getting lost. However you can help to orient yourself by placing your torches in a consistent manner, such as only on the right hand wall or floor while going deeper. In this way you can walk with the torches to your left when you wish to leave. You can also make a very noticeable and unique way to show where you came from, like placing a Redstone torch from the way you came.

Drifting can be effective in finding dungeons if there are mob sounds audible at a dead end.

Note: As of version Beta 1.8 most dead ends have been removed although some still exist.

Mineshaft Mining
This is similar to cave mining, but takes place inside Abandoned Mine Shafts and resources are plentiful. This too has a great return on investment.

Compared to cave mining, the difficulties are that it's easier to get lost in mineshaft tunnels as they look very similar and pre-placed torches make it harder to know which places you have already explored. In addition, abandoned mine shafts contain cave spider spawners which are rather difficult to reach and destroy.

For upsides, due to pre-placed torches, the presence of hostile mobs is much lower. Since supports of tunnels are largely made out of planks, the need to surface due to wood shortage is much lower. In addition, mineshafts contain broken sections of rails and treasure chests full of loot.

Some techniques to prevent yourself from getting lost are: to remove everything from the tunnel, leaving only a 3x3 tunnel. This makes it much easier to recall where you've been, although it takes quite a bit longer; or to leave a unique block behind you, such as wool, so you can know where you traveled.

A very efficient way to never get lost, although it consumes much inventory space, is to put a sign at every branch you encounter. The sign must point towards the exit or towards the last sign (put "--->" or "<---" as text on the sign).

However, the best way is still the old fashioned "right-hand rule" way, in which you place torches on the right side of the walls, thus exiting with the torches on your left side. To adapt the rule to mineshafts, where there are four-way intersections with four pillars of wood, simply place the torch on the first right pillar as you approach it, like you would on a wall. Then when you try to find your way out, once you reach an intersection, just go through the way with the torch.

Shaft Mining
Also known as Vertical Mining and Shafting, Shaft Mining consists of digging your own tunnels to expose hidden resources. While doing this, make sure to be careful as you might remove a block holding back lava or separating you from a drop or hostile mobs.

Staircases
Staircase mining is a common mining technique for quickly reaching lower levels of the map while continuing to gather Stone. It essentially consists of mining downwards in such a way that the player can always climb back up to the mine entrance. This has the advantage of not requiring ladders or other means of getting back to the surface.

Straight
The most basic strategy is to mine in a straight line at a 45° angle downwards, moving one block across for every block down. For added efficiency while climbing back up, dig out four blocks above each step instead of three. Using this method, you won't hit your head with each jump up the steps. Another good strategy to use is to place a torch every 10th block, this way you can know your elevation and when you are likely to encounter lava. To climb back up these stairs afterwards, you only need to hold down the jump key while moving forward.

After enough cobblestone (bricks, or wood) is collected, you can craft Stairs and place them at your downright tunnel. It will make the trip a lot smoother, easier and faster without any need to jump. Although an extra block from the ceiling of the staircase will need to be removed to accommodate the stairs.

Alternatively, you can dig diagonally. Face a corner, and imagine that the corner block is the missing block of a 2x2x2 cube. Now dig that cube. Repeat, adding torches at every step. This mines more resources while also providing the diagonal directions, as opposed to the cardinal directions. This method is very useful for obtaining cobblestone. As all of these strategies are simple and not very time-consuming, you will be able to get to bedrock very quickly.

Spiral
Spiral staircases are slightly more complicated since they have frequent turns, but have the advantage of leading straight down. They also have the benefit of being more contained, giving you a more targeted dig, and being able to reach bedrock quicker and safer.

3x3 Spiral Staircase
One design is a 3x3 horizontal grid. By digging one block down at a time, and moving around the perimeter of your 3x3 area, you will have enough head room as you move down the staircase. You can optionally leave the central column for a barrier or remove it to place ladders centrally, but it isn't necessary for the functionality of the staircase. You can also add stair blocks to this setup as well. Additionally, you can remove the central column of the staircase when you finish, and flood the bottom so you can jump to it and save time going down.

If the center column is removed, then you have a light source but no safety guard; be careful not to fall.

This design drops 8 layers per full turn.

2x2 Spiral Staircase
This is the same as the 3x3 design, however your area is a 2x2 section, meaning there is no central column.

You could also dig off of every tenth front right block(or back left, It doesn't matter). This increases your chances of finding ore.

This design drops 4 layers per full turn. Since you need 3 blocks for travel, and one for the floor, running into gravel will require you to place dirt or cobblestone in its place.

5x5 Spiral Staircase
This is similar to the 3x3, except that you dig out the edge of a 5 by 5 grid. The center column is cleared, acting as a supply of light on the way down. The middle acts as a safety barrier, and the outer ring has the staircase itself. The middle can also be hollowed (digging straight down should be safe so long as you didn't find any caves or lava pools as you made the staircase) out and a ladder can be placed in it with small door ways at different levels to allow for quick and easy access. With this method the hunger bar is preserved better as climbing ladders does not deplete hunger unlike walking and jumping used to travel the outer ring.

This design drops you 16 layers each full turn, and provides an exploratory dig over a wider region. At the same time, it has a bigger chance to miss things in-between the spirals.

TNT Drop
A TNT drop is similar to the traditional method of digging a vertical tunnel to bedrock except for the fact that after dropping to bedrock you fill the tunnel with TNT and in this way raise yourself to ground level, where you ignite the TNT. The actual practicality of it is questionable, as the miner is digging straight down, however if he is interested in collecting the resources then it is usually accompanied by a side tunnel leading to the bottom which the miner can use after the explosion has occurred to collect the fallen ores.

Vertical shaft mining
Vertical shafts are mined vertical tunnels used to gain access to underground mining sites. They can be of any widths starting from 1x1 blocks.

1x2

 * 1) Pick a place where you want your shaft
 * 2) Mine a first block adjacent to the block you are standing at
 * 3) Step down
 * 4) Mine a block you were standing at and one below it
 * 5) Place a ladder every block (as of Beta 1.5 you cannot go up ladders with gaps)
 * 6) Go to 2.1
 * 7) Continue in above pattern until you reach desired depth. From then on use a horizontal mining method of your choice

Mining in 1x1 shafts can be extremely dangerous because of the risk of falling to a cliff in a cave or lava lake. The safest vertical shaft is a 2x2 or larger, as it allows more of a margin for safety and allows you to place torches opposite the ladders to light the shaft up.

3-in explosions
3-in explosion mining is the preferred method of using TNT to mine (although TNT mining is not recommended since it is very dangerous and it is hard to get the gunpowder for TNT). You find a solid stone wall, mine 3 blocks inward, and then you place 1 block of TNT on the 3rd hollowed out space. Once placed, with flint and steel in hand, you right-click it with the flint and steel and back up a few steps and QUICKLY block off the front of the hole with one block of stone. The explosion should create a perfect 4x3x3 hole. Repeat as desired.

A much faster (but risky) technique is mining in a small alcove, filling it with multiple units of TNT, and igniting it, creating a fairly large cavern.While this variation uncovers a large number of blocks at once, the explosions destroy most of the blocks, potentially including valuable ores, and the explosion can let a large amount of lava to leak in, making the cave hard to access and burning any blocks spared by the explosion.

Water-Drop Shaft
With a separate ascent shaft, getting to the bottom can be extremely fast; you simply fall into a water pit. Ascent is accomplished with a ladder. This arrangement can be accomplished by first stockpiling about 64 ladders along with 2 water-filled buckets, and then excavating a 3-block wide shaft. One side of the shaft becomes the water pit, while ladders are placed in the other side. The middle is then filled in to prevent falling outside the water pit while descending.

For detailed building instructions, see Vertical Mine Shaft With Water Drop.

Absolute Ore Mine
Things needed: 256 wood planks


 * Step 1: Get the wood (64)
 * Step 2: Make The wood into planks (256)
 * Step 3: Make 2 Wood Picks.
 * Step 4: Go to an extreme hills biome (better chance of finding emerald (optional)) and Get 6 Cobblestone. Keep in mind that emerald will be released in 1.3.
 * Step 5: Make it into 2 stone picks
 * Step 6: Get 6 to 9 iron. Make 2 to 3 iron picks.
 * Step 7: Turn your lighting up on your display settings.
 * Step 8: Go down to y: 12.
 * Step 9: Make a big cave around you, not going any deeper than y: 10.
 * Step 10: mine more around you.

Finished results:

You have:
 * Leftover wood,
 * 1 1/2 Wood Picks
 * 1 1/4 Stone Picks
 * 1/3 Iron Pick
 * around 40 redstone
 * about 19 iron ores
 * some 3 or 4 iron ingots
 * very little emerald if any.
 * very little gold if any
 * very little diamond if any.

If a dungeon or an abandoned mineshaft is found, destroy it. it will get you some resources. Be weary of the monster spawner that will be in the dungeon.

Safety
Horizontal mining is not as dangerous as vertical. But there are some similar suggestions. Carry a water bucket and some blocks of some disposable, NON FLAMMABLE material (ex: sand, gravel, cobblestone) somewhere on your hot bar. A block can be used to quickly plug the leakage in cases of lava, and water can be poured over source lava to turn it into obsidian, as well as to put out fire.

Terms and Definitions
main shaft/access shaft: a 1x2 or 2x2 tunnel use accessing other tunnels.

efficiency: how many ores you get for the amount of effort you put into the mine, or how many ores you get/how many cobble you dig to find them.

Thoroughness: how many of the ores you extract per chunk

The tradeoff: a mine can be made more thorough at the price of efficiency, or vice versa.

Layout: the top-down view of the mine.

Branch: the tunnels dug purely to gather ores.

Branch-length: how many blocks you dig your branches out. One recommendation is to measure a length with the durability of a stone pickaxe.

Spacing: how far apart the branches are.

Completely Thorough: a mine that reveals 4 new blocks/block dug, and reveals every block within a chunk, is completely thorough.

Tiering: "stacking" one branch mine on top of another, in order to obtain a much greater degree of thoroughness without sacrificing too much efficiency.

Efficiency vs Thoroughness
(with a word about thoroughness)

Efficiency, by definition, is how many diamonds (or other ores) you get for how much time you spent reaching them; actually accounting for time spent getting to the mine is difficult, so ores extracted/stone mined is a more useful term.

Thoroughness is what percentage of the ores you extract from a given chunk.

Unfortunately, efficiency is often crudely approximated by blocks revealed/block mined, while thoroughness is crudely approximated by blocks revealed/chunk.

Since both include "blocks revealed", they are often confused, which is a BIG mistake.

For simplicity, let's assume that all ores spawn in 2x2x2 cubes or smaller. then, there is absolutely no need to reveal every block; in fact, a spacing of three, followed by a tiering distance of 4, will then be completely thorough.

Now, let's assume that 90% of ores are 2x2x2, but 10% are 1x1x1; while obtaining 100% unitary thoroughness then requires a spacing of 3 and a tiering distance of 2, the original mine (the 3-space 4-tiering) maintains a thoroughness of 98%-not that bad a decrease. now look at the EFFICIENCY of the two mines; the 100% thorough mine requires mining TWICE as much stone in exchange for a paltry 2% increase in total yield, resulting in, essentially, HALF the efficiency.

In order to give an actual number for efficiency, we can use efficiency=100*(number of ores collected / number of blocks mined)-or, equivalently, %efficiency = (number of ores collected/number of blocks mined)

This equation is similar to a real-world mining calculation such as grade = (grams of metal/tonnes of rock removed). Nowhere in the above equation is "observed" blocks mentioned, and so it is a red-herring to aim for maximum blocks observed. This simple equation leads to a conclusion about the most efficient way to mine in Minecraft. Several assumptions must be made:


 * 1) Ore is distributed randomly
 * 2) Ore is orientated randomly
 * 3) Ore occupies a certain width, whereby two tunnels running too close to each other would intersect the same orebody twice.

In Minecraft these assumptions are essentially true, though there is some distortion since diamonds only spawn once per chunk (?).

So we reach the crux of the argument; tunnel spacing. In the traditional "efficient" mining methods, tunnels are spaced close together in order to "observe" the maximum number of blocks possible, therefore removing all of the ore from an area. So, let's consider a spacing of 1; that is one tunnel separated by one block from another tunnel. During the digging of the first tunnel, several ore bodies are encountered. This tunnel has a high efficiency (in fact, the maximum efficiency possible, as we shall see later). The second tunnel has a very low efficiency because almost all of the ore bodies it encounters have already been removed by the first tunnel. This causes the efficiency of the mining operation to plummet. A spacing of 1 is incredibly inefficient. Now we move to a spacing of 2. This is a spacing that a lot of people use because it leads to 100% observed blocks in a single layer. However, with a spacing of 2, the second tunnel still encounters several ore bodies that have already been removed, so it is also quite inefficient. We can go on like this; as long as the second tunnel has a chance of encountering ore bodies which have already been removed by the adjacent tunnel, it will have a less than maximum efficiency. It follows that the most efficient way to mine is to place the second tunnel far enough away from the adjacent tunnel that there is no chance of encountering ores that have already been removed.

You don't have to take my word for it though. I have modeled the problem in matlab using a 2D slice of a real Minecraft level and a virtual mining procedure. The model mines a 1 block wide tunnel through the 2D layer and removes all diamonds it encounters, just like a real player would do. The model is limited to diamonds but the principle applies to all ores. It repeats the mining for different tunnel spacings, from 1 to 10. The model then records how many diamonds were mined for each case, how many blocks were removed, and calculates the efficiency of each spacing. A simple graph is produced:



The results indicate what is expected - that when tunnels are close together they are not efficient because the miner will encounter diamonds which were already removed by the adjacent tunnel(s). A maximum efficiency is reached at a spacing of around 6 blocks (that is, 6 solid blocks left in-between the tunnels). At this spacing, efficiency is about 0.017, corresponding to 1.7% of blocks removed being a diamond. At this spacing, the tunnels effectively become independent of each other and so, statistically speaking, the chance of encountering an ore are maximized because there is no chance the ore has been removed by an adjacent tunnel. Above a spacing of 6, efficiency does not increase greatly because ore collection rate is simply a function of the distribution of ores within the level. Note: in the above graph, efficiency appears to drop-off at a spacing of 10. This is simply a limitation of the size of the level used to model the process, resulting in a large error at high spacings. If a larger level were used, the line would smoothly come to a maximum efficiency and stay there.

In summary:


 * 1) The term "efficiency" is often applied to the practice of making every block observable, however this is not usually the objective of a miner.
 * 2) A more practical definition of "efficiency" describes the percentage of blocks removed that are ores, in other words efficiency = (ores removed / blocks removed).
 * 3) Maximum efficiency is reached when adjacent tunnels become independent of each other, since there is no chance that an adjacent tunnel has already removed an ore.
 * 4) This maximum efficiency, for diamonds, is reached at a spacing of 6. Since other ores are usually collected in copious amounts compared to diamonds, this spacing is recommended for every-day mining operations.

Branch Mining
Branch mining consists of mining out side tunnels from an access shaft to expose as many blocks as possible with a minimum of blocks removed.

layout 1
(antennae layout) An effective technique if you want to find rare resources with minimal effort. It is basically mining down to any level, usually to bedrock, and then mining outwards to the sides, much like a tree with a trunk and branches.


 * 1) Use the staircase method to dig down to bedrock.
 * 2) Go up 2 blocks and fill any space below you mined out.
 * 3) Dig a 3x3 room.
 * 4) Dig a straight 2x1 tunnel in a straight line then dig out 32 blocks every 4th block.
 * 5) To further increase efficiency, you can end the 20-block tunnel by digging 4 blocks of an 1x1 tunnels as each of the mined block reveals more than a 2x1 tunnel.

This method is based on the relatively low probability of desirable blocks being created without any neighbors, so it will occasionally miss small/narrow ore deposits that fall entirely between the branches, but it covers ground faster, so you'll usually get more ore for your time. If you'd rather be sure of 100% coverage, simply place the tunnels closer together. it is also meant to be done quickly.

Diagram: X = Tunnel "Trunk" B = Branch S = Staircase Y = Outpost (for supplies etc.) B      B                 B       B           B       B                 B       B           B       B                 B       B           B       B                 B       B           B       B                 B       B           B       B                 B       B           B       B       YYY       B       B X X X X X X X X X X X X X YYY X X X X X X X X X X X X           B       B       YYY       B       B           B       B        S        B       B           B       B        S        B       B           B       B        S        B       B           B       B        S        B       B           B       B        S        B       B Each branch can be any length, but about 32 blocks long is a good length to begin with, as it can be measured with the durability of a stone pickaxe.

layout 2
(pinwheel mining system.)

the pinwheel mining layout:

the pinwheel mining layout is designed to cover HUGE squares of land-over LONG periods of time.


 * 1) get to the diamond layer by your preferred method,
 * 2) dig out a room-as large as 10x10x8 if you want to set it up as a self-sufficient base, or as small as 4x4x2 if you just want to get mining. (use even numbers if you like 2x2 access shafts; odd numbers if you prefer 1x2 access shafts)
 * 3) mark the access shafts into the middle of the walls; the picture shows 2x2 tunnels. (if you do not use the wide tunnels, mark the main shafts with signposts.)
 * 4) dig a given access shaft out until your inventory is full. (you'll have plenty of chances to get the ores out of the access shafts)
 * 5) note: If you use a simple straight staircase to get down, you may need to leave off the south tunnel for a while.
 * 6) mark the branches at the desired interval. The picture shows a spacing of 2, which is 100% thorough but inefficient.
 * 7) dig out each branch until your inventory is 3 spaces away from full, then turn around
 * 8) On the way back, place torches in any dark spots, and collect any missed ores-collecting all the coal is advised, but not required.

As always, you can use any spacing; a spacing of three provides both reasonable efficiency and reasonable thoroughness.

This layout can compete with the phoenix mine in terms of efficiency, and is easier to modify if necessary, but it does require a lot of time for each trip.

layout 3
(room and fork layout)


 * 1) Dig a room that is 7 blocks long, 10 blocks wide and 3 blocks high. Have your stairway/ladder in the middle of one of the 10 block walls, preferably 2 spaces wide.
 * 2) Starting in one of the corners, dig parallel to one of the walls of the room you just dug, for 20 spaces, placing a torch every 5 blocks.
 * 3) Then, dig another 20 block tunnel that has two blocks between it and the previous tunnel.
 * 4) Continue until you reach the other side of the room.

Diagram:

Key: A = Air B = Stone block S = Staircase T = Tunnel A A A A A A A A A A T T T T T                 A A A A A A A A A A B B B B B                  A A A A A A A A A A B B B B B                  A A A A A A A A A A T T T T T                  A A A A A A A A A A B B B B B                  A A A A A A A A A A B B B B B                  A A A A A A A A A A T T T T T                  T B B T S S T B B T                   T B B T S S T B B T                  T B B T S S T B B T                  T B B T S S T B B T                  T B B T S S T B B T

By utilizing this variant properly you can uncover all the blocks in quite a large area, and the mineral yields are quite high. Having the stairs 2 blocks wide allows for thorough strip mining as they can be strip mined around. Also, a good length for each tunnel is 20 blocks long.

Tiered Branch Mining


Tiered branch mining is the art of stacking shaft mines on top of one another.

If you decide to stack your mineshafts, however, you should use an odd-spacing, or you'll get inefficiency AND blind spots.

for instance, The following tiering has the advantage of being very efficient, while finding any 2x2x2 cube of valuable ore. It has the disadvantage of missing some of the smaller veins, though it doesn't miss as many as you might expect-it yields somewhere between 80 and 90 % of the ores in a region. (mine at y=12, y=16, and y=8)
 * oxoooxoooxooo
 * oxoooxoooxooo
 * ooooooooooooo
 * ooooooooooooo
 * oooxoooxoooxo
 * oooxoooxoooxo
 * ooooooooooooo
 * ooooooooooooo
 * oxoooxoooxooo
 * oxoooxoooxooo
 * ooooooooooooo
 * ooooooooooooo

(bedrock begins.) (x=branch, o=stone)

This is a good mine for single player if you can't stand the mere possibility of leaving a 2x2x2cube of diamonds just below or above your initial mineshaft-this will find them.

The next one has a tiering distance of 3, and is noticeably less efficient in terms of ores found/cobble removed, but it finds at least 90% of the diamonds in a chunk:


 * oooxoooxoooxo
 * oooxoooxoooxo
 * ooooooooooooo
 * oxoooxoooxooo
 * oxoooxoooxooo
 * ooooooooooooo
 * oooxoooxoooxo
 * oooxoooxoooxo
 * ooooooooooooo
 * oxoooxoooxooo
 * oxoooxoooxooo

(bedrock begins.) this is a good mine for somewhat crowded multiplayer, where thoroughness is actually worth something.

should you be willing to sacrifice efficiency in exchange for revealing every last block, you can use a tiering distance of 2:


 * oooxoooxoooxo
 * oooxoooxoooxo
 * oxoooxoooxooo
 * oxoooxoooxooo
 * oooxoooxoooxo
 * oooxoooxoooxo
 * oxoooxoooxooo
 * oxoooxoooxooo

This particular tiering, however, is not only inefficient, but requires one of the access methods shown in the pictures-either an 8 tall, 2-3 wide tunnel with staircases as shown in the grey picture, or with one access shaft for 2 sets of layers. this should be used only in ridiculously crowded multiplayer servers, when what matters is finding that one redstone vein that got missed by all the random-miners.

however, nearly any spacing and layout can be used with a given tiering distance. , as it is fairly thorough, only slightly less efficient than a straight shaft, and it can be transformed into nearly any level of thoroughness without wasting effort.

however, Nearly any layout, spacing, and branch-length can be combined with any tiering distance, though doing it with a phoenix mine on the compact spacing is NOT recommend for anyone who gets headaches easily.

Simple Strip Mining
My technique is to take off the top 6 layers of a mountain completely. Continue until your mountain is entirely flat. TNT is useful for the first 5 layers, since the explosion will destroy only cobblestone for the most part.

Diagram: Key: A = Air B = Block L = Ground Level

Step 1: A A A A A A A A A A         A A A A A A A A A A A A        A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A      B B B B B B B B B B B B B B B B

First 5 layers are gone when you start mining.

Next couple steps are as shown:

A A A A A A A A A A         A A A A A A A A A A A A        A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A      A A A A A A A A A A A A A A A A    B B B B B B B B B B B B B B B B B B

A A A A A A A A A A         A A A A A A A A A A A A        A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A        A A A A A A A A A A A A A A A      A A A A A A A A A A A A A A A A    A A A A A A A A A A A A A A A A A A  B B B B B B B B B B B B B B B B B B B B B

This time consuming method is a useful tool for when you need minerals or a flat area.

Quarry Mining




Quarry Mining is very similar to branch mining, sharing the prospect of taking all resources within an area. These mining shafts are used very commonly in minecraft. The difference between Quarrying and Branch Mining is that the process of Quarrying involves a large rectangular or square strip, continually mined downwards with a staircase running along the side. This method got its name by its similarity to real world quarry sites. Quarries are typically ceased when a large cave is discovered (This does not directly stop the excavation, it just makes it difficult to continue), the miner abandons the Quarry for another project, or bedrock is reached. One can place a minecart track(powered) in a spiral, to allow ease of access.



The Construction of a Quarry is as follows:

1: Determine the size of the project, there is no standard so simply choose how big you want it to be, however it is advised that the area is large, to maximize resources within a single quarry. (A typical quarry can be 20x20 or 20x30, for example)

2: Begin Mining until the entire area is one block deep, save for one block which will become the stairs

3: Continue mining one block deep while keeping an extra block to extend the stairway, until the mine reaches bedrock or until you wish to abandon the project.

Example:

Key: - = Air B = Stone block S = Staircase

Top of mine:

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BSB B-B B-B B-B B-B B-B B-B B-B B-B B-B B-B BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

Next few levels down:

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB B-B BSB B-B B-B B-B B-B B-B B-B B-B B-B B-B BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB B-B B-B BSB B-B B-B B-B B-B B-B B-B B-B B-B BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

Although the yielded amount of cobblestone, dirt/sand, coal, iron, and to some extent gold, will be enormous, and the possibility of lava is very high, this is not the best method for mining diamond and lapis lazuli, because they're found only at the bottom of the map (Note: Diamonds and Lapis Lazuli CAN be mined using this method, but due to their rarity the placement of the quarry along with its size will determine the amount). This type of mining is suggested for getting large amounts of cobblestone, iron and coal, besides the ability to gain large amounts of resources, this type of mining exposes many caves for further exploration/mining.

Besides mining, Quarries also offer some non-resource related benefits, such as keeping the area clean and fresh (not ruining the nature), and service as a handy trap.

Water blocks placed two high at the bottom of a quarry can allow quick descent (by just jumping into the water), and water elevators can be used to quickly return to ground level from the bottom.

Warning: Be extremely careful around this mine, as a fall will surely be fatal, unless you covered the 2 bottom levels of it with water. Make sure the shaft is either covered up by a layer of blocks or a fenced perimeter. The shaft should also be well-lit to avoid being a mob pit.

Tunnel-mining
This involves digging a long tunnel. You will need a lot of wood (for sticks), and optimally, crafting tables, chests, and furnaces. The simplest tunnel is 2 high by 1 wide, but the wider and higher the tunnel, the more cobblestone you get per chunk you explore (you will not gather cobblestone any faster, also you will get less ores). Dig at about level 50 if under land; 40 if underwater; or 12 if for precious ores. You may want to use the cobblestone to seal off caves already explored. This is like a quarry - but more useful since less resources are spent going through the dirt/sand layer, and it can also be used in conjunction with minecart tracks to go from one base to another. A 4X3 tunnel that is 1800 blocks long will yield as much as an 18X18 quarry to bedrock, though arguably safer as you won't hit the lava layer, and it will yield more diamond/redstone if at layer 12, as well as the fact that falling in is completely non-lethal!

A 2x1 shaft is probably the the highest-yielding way of mining... for ores that is. Mathematically, a 2x1 shaft reveals 8 blocks for every 2 blocks mined forward, so the basic premise of this system is that digging little 10-block deep side shafts off of your main tunnel, as in branch mining, does not yield any more ores than digging straight as your yield will be highest if you simply keep moving forward and mine endlessly instead of stopping a 2x1 shaft will also lead you into plenty of caves, which could be good or bad depending on how you feel about those. A good strategy for cave run-ins is to make a quick run-down and nab any visible ores, then find your shaft and keep moving. If you don't want to walk all the way back home after digging this, just dig in a "U" shape until a little less then half of your pick is used up, move 8 blocks to the side, and go back. The 2 biggest problems with this kind of mining are: A. It takes a lot of torches, though your coal yield is way higher than the amount you spend on torches, and B. You cover a lot of distance, therefore your chances of having lava run-ins are pretty high.

Multi-mining
The name fits any combined mine such as the following:

Quarry-Branch Mine
This involves digging a quarry and adding ledges every few blocks down around the outside while digging. The sides of the quarry have to be a certain length, for example with a two-space branch mine, you need each side to be [(something divisible by 3) + 1] blocks long. The result will vaguely resemble a shopping mall atrium with one massive open space and then a bunch of "shelves". Then, dig the shafts to at least 20 blocks for a ton of ores, including quite a few diamonds (about 3 veins) down on the lower levels. For a 10x10 quarry, you will get about 150 stacks of cobblestone, while for larger mines (e.g. 40x40) you will get around 2000 stacks, handy for massive building projects.

Quarry-Cave Mining
Dig a quarry down to under Y-level 25, and attempt to unearth a cave. If you do, you can explore that cave. Many of the deeper caves have no surface entrance, and being able to expose a cave that is otherwise sealed to the outside world through a quarry can garner you both large amounts of cobblestone, dirt, and gravel, as well as the rewards of mining out a deep cave. If you don't want to hold on to the stone that is excavated, you can use it to fill in dead ends, allowing you to navigate the remainder of the cave more easily

Quarry-DropShaft Mining
This involves basic quarry technique but in small squares. First you decide how large you want your mine to be. For example I would use a 2 by 2 square quarry, so I would make a 3 by 3 hole then go over 1 block and repeat. And this allows for maximum ore exposure. But you would need at least a 3 by 3 squares, going all the way to the bedrock. WARNING: this can be very dangorus, as you can run into hidden caves, dungeons, lava pools, and abondoned mines.

"Mass Mining"
For those who favor mining in a straight path but try to not make it very long. Once you reach bedrock level, go up a few blocks and start mining and make it a large corridor. If you reach a cave, continue to make the large corridor (but secure the cave first). This will give you large stores of cobblestone and more of a chance of finding lava. Find ores that are nearby that would be hidden if you did another technique and did not get lost in your mine. This a very basic technique yet a tiring way of mining. It is suggested to use a diamond pickaxe with max efficiency enchantment and unbreaking enchantment so that the pickaxe doesn't break during the process and also consumes less time compared to using a non-enchanted stone pickaxe.

Aesthetic Mines
This section is for mines that focus more on aesthetics rather than efficiency.

Clc's Vertical design
A mine of mine (No pun intended) I decided to talk about, seeing as how few aesthetic mine designs there are it should be a welcome change. Mind you don't expect to do all the connections, let alone open/maze connections (Variations section) unless you're on a server, or you have a will you can break diamond on.

Design
This design consists of a Hub and a Push leading into another Hub.

Key:

B - Block

_ - Air

Hub: Top view:

BBBBBBB

BB___BB

B_____B

B_____B

B_____B

BB___BB

BBBBBBB

Side view:

BBBBBBB

BB___BB

BB___BB

B_____B

B_____B

B_____B

BBBBBBB

Each push is basically the design behind it (The side view) dropped a square repeated several times, the amount is dependent on the miner but an even number is preferred due to torch placement (Discussed later) The central hub (The first hub made in the mine) will have 4 pushes in each of the cardinal directions, eventually, if you are in need of ores you may choose to go down in one direction until you have what you need. I recommend you check your y coordinate about now, you may want a push length that will allow you to get your y value as close as you can to 12 (Lava spawns in caves at 10, and your y is up 2 for the positioning of your head) After you've decided on your length and finished a push you make another Hub in the same size as above. Continue until you reach the last of your hubs (You should end it before you hit bedrock, otherwise it won't be very nice looking)

Torch Placement
Torch placement is simple in this design. You will have 8 torches in each hub, on both sides of the bottom of the corners. If you want you may add a torch to the center floor to add more light, but it is enough to prevent mobs spawning as it is now.

For every push you put two torches on every other left and right hangs.

Connections
After you finished all of the cardinal pushes you'll be wondering what next to do, considering the amount you've mined you may want a place to store away items, connections are great for this.

Each connection is a hub formed by two of the cardinal branches intersecting, meaning if you went to the first north hub down, you'd have to mine one push/hub to the left and connect to it from the first west hub down by pushing right. It's the same as the hub but it leaves two walls with nothing to do, if you try to continue with them you will get intersections that are hard to make aesthetic unless your looking for a large open mine, or a maze mine. Instead, you can use it for chests, and it works well for it's purpose. Very hard to describe with letters, so here's a picture instead: Picture

Continuations
After your cardinal directions are done, you have your as many connections as you care for, what's next? You continue Adding onto your bottom hubs, only with straight pushes. The bottom hubs will branch in all directions except backwards (Unless your going with a open/mine variation) and each of those hubs may spread in the same direction so long as it's not backwards for the original hub. If you positioned well in the first central hub and push size, you'll be scraping a long in a fairly wide tunnel along the same height you find diamonds. It's easy sailing from here on.

Variations
Central Drop shaft:

Central hub is under an area of flat ground, you put a three deep hole where torches will go, ladders go on the bottom and top, torches in the middle, you go above the hub as normal only there will be a 2 high gap under the hangs on this first hub to allow for the ladders as a way up. Due to update you will need the ladders to go all the way down, and such won't have a place for a torch. You can circumvent this by putting them on the middle of part left over at the top of the next section, the lighting is the same and you won't need an extra torch to prevent mobs spawning. This also works particularly well if you want to replace the top with glass.

Open Mine Connections:

Same as original, only every connection you make splits off in all four directions. It goes up with a 1 wide path in the center in all four directions and the both of the two wide paths go down until they merge (Which is when it can do so without getting rid of the upward path)

There are two variations, one where you will go up when you make a connection, so you will have a stack of hubs in all directions, another where you only dig down in the connections, where they intersect you build the 1 central path down to the hub. The latter is more efficient as all of it will eventually lead to the bottom and therefore be mining ore.

Maze Mine Connections:

The same as an Open Mine except your down path is one wide, not your up path. Same two variations, same correlation in efficiency.

Lava lights:

You can replace the torches in the center (If you placed them at all) of the hubs with a piece of glass and lava under it and it gives only one light less. You can change it for a 3x3 if you feel so inclined and have enough lava.

Drop Shafts:

This combines the Central Drop Shaft and optionally the Open and Maze Mine Connections. It requires close tallies if you don't want to combine them though.

At your Hub you mine down the same as if you were going to make a Central drop Shaft, but continue until you are on the same level as your next hub (Depends on the size of your push, like a 8 push would be 8 blocks down) After you reach the bottom you make another hub in the same style as a Central Drop Shaft. This will require more ladders, so it's not a very good idea if your short on wood, but it allows a certain maze quality that I find welcome.

There are two places where you can put the ladders, but the two per corner type of the Central Drop Shaft style is preferred, however the other style uses less ladders. You mine your shafts in the blocks directly north/south/east/west of the center so that you have 4 shafts all the way to the next hub, this require 5 blocks to hang down from the hub, some like it, others don't.

Two variations on top of that, you may use the drop shaft for all your hubs, thus any hub with a hub above will be able to ascend, or you can only use the shafts for the central hub, adding 'terraces' to your mine.

Where does open/maze mine connections come in? After you get down to the bottom level you may continue to stretch out and connect with the original push/hubs. Once you connect you may use the open style, leaving 1 wide path up or the maze, leaving 2x2 wide up.

Central Mine

 * is open space;


 * are rails

Once every x blocks you should change the rail/torch/rail combination for a Powered Rail/Redstone torch/Powered Rail

You will have a central rail system with smaller hallways for pedestrian traffic. On interesting locations, you should add some kind of rail station with access to the rail.

Connections
(From the top)

Random Mining
Mining randomly is very simple: dig, dig, dig wherever and however you just happen to feel like digging at the moment.

Very simple, and potentially the most rewarding type of mining around: you can find dungeons, massive cave networks, and maybe the enemy base. HOWEVER! it is also, potentially, the least rewarding: you could be 2 blocks away from a 16-ore diamond vein (two cubes, from 2 different chunks) and have no idea. As with many other methods, it's possible to miss all the ores, as this method offers little consistency.

Random mining can very well be the most dangerous method. you can get lost, mine your way into lava (and thus lose your items), into a ravine, into a skeleton spawner with 5 angry skeletons, or even into your own 40 block drop. Alternatively, you could embarrass yourself by mining straight up into a patch of gravel or sand, or flood your mine by digging into the ocean.

It is worth mentioning that forming a path directly to diamond in this manner will often earn you a swift ban on most servers for using an X-Ray mod.

That said, there is one major benefit to random mining; it will confuse potential griefers. Surrounding a main base with all kinds of twisty passages is a viable option, though it won't ultimately stop a determined griefer from finding you or your base.

Piston Mining
Piston mining is a technique for safely extracting small amounts of valuable ores, usually diamonds, and for inserting 'windows' into potentially dangerous spots.


 * 1) Start by digging a 1x2 hole in a safe spot a few blocks to one side of the target area. If no truly 'safe' spot is available, pick the location where the risk is least.
 * 2) Place a block and a piston in the hole. Any block moveable by a piston will do. Glass would allow you to see hazards without triggering them. An efficient method is to place one block of glass, then use 'filler' material for the subsequent blocks.
 * 3) Dig another hole a few blocks to the other side of the target area, ideally in another safe spot. When doing this, don't forget that the maximum distance a piston can push is twelve blocks in a straight line.
 * 4) Activate the piston using a redstone torch, lever, button or pressure plate as you prefer.
 * 5) Insert another block, re-open the 'receiving hole' if necessary and reactivate the piston.
 * 6) Repeat until the ore can safely be collected, or your glass block has revealed a hazard or confirmed all is safe. Not that you may need to check several rows before you can be entirely sure there is no danger.
 * 7) Retrieve the piston for reuse.

This mining method is only practical for collecting very small amounts of ore, but it can be useful for collecting diamonds from dangerous spots or when you suspect a natural hazard is nearby and you want to locate it precisely.

Space/Portion Mining
Not to be confused with Strip Mining; however, this does involve a similar method.

Room Mining
This form of mining involves someone to make a hall way and then make a small opening in the wall. From there, one must simply dig out a portion of the block to create a space. This method is repeated many times down the hall on either side to create rooms for various purposes, while finding several ores and valued materials in the process. This method is useful for the creation of houses, barns, indoor-gardens, storages, and in the creation of hard-to-find/secret places as it offers a variety of places one may go to in order to find something, but they may likely give up in the process unless they are determined.

Tunnel Mining
This is highly similar to Room Mining, except that instead of Building rooms, you build tunnels. However, this takes much longer to do and tunnels are usually much larger than rooms. Because of this, Tunnel Mining is lesser to be used as the tunnels take up many tools in the process of making them as well as the mining process may dig into a body of water and flood the tunnel. However, if the player wants to make an artificial river for boats, this may not be a problem. Despite the fact that they may yield many resources, players may use up several pick axes or shovels in the process of making them as well as torches to light up the tunnel. Players may get bored of doing this and may abandon the tunnels while still in the process of making them. Some may not consider beginning construction on future tunnels due to lost supplies and the tunnel not being rewarding enough to continue. This method is useful for making minecart subways, large indoor-gardens, art galleries, tree farms, boat rivers, large barn(s), mazes, doing construction on vertical and horizontal structures, constructing strip mines, and secret/hard-to-find areas by making tunnels that seem to go nowhere.

Clear Mining/Safe Mining
The general purpose of Clear Mining (or Safe Mining, whichever one may prefer to call it) is a variation of Box Mining and other simple techniques. A player first finds a suitable area, preferably one block above the bedrock layer so that the player can easily obtain diamonds and other rare minerals. The player must also have at least 5 to 6 stone picks, one iron pick for rare minerals such as gold, and 3-4 shovels for gravel. A sword is optional depending on the players preferred difficulty settings. Once the player has found a suitable and deep area that they are confident in they may either begin or set up a small chamber near the area to store minerals and construct tools to further their mining. To begin, make a simple 1 block wide and 2 blocks high that spans roughly 8-10 blocks in length. Once this has begun, the player then uses their stone picks to mine directly in front of them where their tunnel ends, but, there is a catch. The player does not move once they make their initial 8-10 block tunnel, and mines only the above block of the two block height making a small box, 4 blocks long. Once the player makes a half tunnel 4 blocks long, the turn to their left or right and do the same; not breaking any of the blocks below the first block. (when done the concept is much more simple) After the player makes a reversed "T" shape, then the player can start to mine out the remaining areas around the tunnels, only using their reach length to clear away stone and any materials. Once the player has maxed out their reach length, they will be in small "box" that reduces risks of being suffocated by gravel or possibly lava. The player then should have a clear area, and then mines out the remaining second blocks, still avoiding the "edges" of the safety box. Once all materials are mined, the player can then break the box and gather the resources in one quick run. Once the player is done in this, there will of course be small "edges" that they not reach, and these should be mined out making a clear box. To further the effectiveness of this strategy, one may then place torches in the "frontal" corners of the area and repeat the process on each side, however this time, rotating their view to clear away all areas of their reach, so long as they are away from their initial entrance tunnel. The end result should be a very fast, resourceful, and safer approach to mining at bedrock. However, mobs may spawn in areas of the mine that are poorly lit, and lava is a factor, along with tediousness, so the player must make a commitment to a clear mine, leaving when satisfied with their bounty of materials. Like parenthesized above, this strategy is best played out rather than explained.

Amphitheater Mining
Start with a basic U-shaped mine, and make an "amphitheater" down the levels until you have a one-block space. Then, make a doorway ahead to make another amphitheater mine. This is very useful, and you can even make it decorative by adding staircases as stairs or chairs.

Wanderer mining
This is a simple mining technique, but isn't used much because of the risk of getting lost. Start by making a staircase down until you reach the level where the desired ore is most commonly found, and begin mining. Occasionally change directions and make multiple branches.If there is a rise, plow through it. If there is a fall, bridge it with cobble. the point is to cover as much area without changing your y coordinate.

Worst Case Scenario
If you fall into Lava, do not panic; try to get far away from the lava. This way even if you die, your stuff won't be destroyed by the lava. If you need to heal, eat Food and hide in a corner/away from Mobs, and make sure you use a bucket of water if you have one. If you know you are going to die anyway press and  to find out your coordinates and take a screenshot.

If you are trapped in blocks and are suffocating, try to dig looking downwards. This could assist you in getting out of the trapped pit.

If you are fighting and are going to die, press then.

Whatever happens, you should look back upon what you did, and analyze how you died, and what you could do to improve.

If your pickaxe breaks and you've stumbled into a cave and you have lost your way the only option is to punch your way out and this could take a while.

Best Case Scenario
Should you happen to accumulate a large amount of resources, such as, perhaps, 2 stacks of Iron Ore and 10 Diamonds you may be tempted to delve further into the cavern. Resist this urge and return to your base to empty your loot. Dumping off your goodies instead of trying to explore longer may help in the long run, and will reduce the chance of losing your loot. Having a bed at the base of your mine is also helpful; if you die, you will spawn at the base of your mine, hopefully surrounded by your chests full of goodies!

Safety
When going for a mining trip, do NOT dig when in a desert or place abundant in gravel. If you dig under gravel or sand, it will fall on you and suffocate you. The only real incentive to mining under a desert is the significantly higher chance to find a mineshaft.

When going mining, after you are finished and you make your way back, try to go out the way you came. That way, you know you are safe and there is no risk of lava, water, gravel, or sand falling on you and killing you. Digging a new shaft to escape the underground could result in sand falling on you when it turns out you dug your exit below a desert biome. Or you could be drowned when the entire ocean floods your exit shaft.

Never take valuable items when going mining. You don't want to delve into dangerous caves while carrying tons of iron and diamonds, for if you lose them while mining, you will be sorry. While you can carry a crafting table if you have an extra one handy, it's probably easier just to carry a quarter-stack or more of wood. Carry more for longer delvings, but don't carry more than you can afford to lose to lava. Any time you reach a good spot for a temporary base, turn one block of wood into a crafting table, then use that to make a chest, and stash anything you don't want to carry with you. (Ores/diamonds, cobblestone/dirt, some of your wood, spare sticks, planks, and so on.) Then go on to replace your tools, and make signs, fences, ladders, or whatever else you need. (Perhaps a furnace, if you need to smelt iron for a new pick, or even a bed if you'll be in danger.) You can take the table with you afterwards if you like -- the chest should leave you with some more inventory slots. Don't take the slept-in-bed! ;-) Normally, you'll want to use stone picks for economy, but carry at least one iron pick for advanced ores (gold, redstone, and of course diamond).  If you have tons of iron and are impatient, you might use iron picks in general, but while those are faster, they only last twice as long (block-wise) as stone tools, and you'll be going through a lot of picks regardless.  Take a diamond pick if you want to be fast and efficient for its durability, or to collect some obsidian.  Never take your diamond sword while going mining, as you know that swords are disposable and you want to make them last, so losing it on a mining trip is pretty sad.

Anleitungen/Minentechniken Tutoriels/Techniques de minage Poradniki/Techniki wydobywania surowców pt-br:Tutoriais/Técnicas de Mineração Шахты 教程/采矿技术