Breaking

Digging is one of the most fundamental activities in Minecraft, performed (by default) by holding the left mouse button while the cursor is over a block. Digging is used to create passages and tunnels, to clear away unwanted blocks, and is also the primary way of acquiring blocks for future placement or crafting.

Basics of Digging
Digging is accomplished simply by the "Attack" control (normally holding the left mouse button) while the cursor is over a block. If you are within about 4 meters of the target (your reach in a straight line is just under 4 meters/blocks; testing shows about 3.975. Diagonally you can reach 2 and 13/16th blocks), you will begin swinging your hand, making a repetitive "thump" noise as you hit the block, and cracks will begin to appear. When you are in range, the block will also by marked with a wireframe cube outline, showing you the current target. After the cracks completely cover the block, it will break, and depending on the type of block and the tool you are wielding you might harvest it for resources.

Although many blocks can be harvested with your bare hands, the harder ones require the use of a tool. In particular, to get resources from stone or metal-type blocks, you will need to use a Pickaxe. For harder blocks like Iron Ore or Obsidian, not just any pickaxe will do; you need one made from sufficiently hard materials. You can also use Shovels and Axes to speed up digging of dirt and wood-type blocks, although they are not required to get the resource drop. The downside is that tools have durability, and so they eventually wear out.

You will continue to dig as long as the mouse button is held down, although there is a slight pause of 0.25 seconds between destroying one block and beginning on the one behind it. You can move freely while digging, and you can even dig while jumping or swimming. Although there is a speed penalty for the latter two, see below. This makes it easy to dig long tunnels or to clear away a large volume of material.

A bad thing that many new players do is dig directly down. This can lead you into falling in a dark cave with no lava as light, getting slaughtered inside a dungeon, or even just plainly burning up in a lava pit with no escape. For similar reasons, it is not recommended to dig UP either, due to the fact that a monster or lava can come tumbling down right on top of you. Another mistake is to stand right next to the wall at which you are digging. If there is a monster right behind it, it will be able to attack you. Also, at lower levels, you might dig into a pool of lava that will spill onto you, but if you stand back, you will have time to turn around and make a run for it.

You lose your digging progress if the target block changes while digging, so it is best to target the middle of a block's face. Progress is also reset whenever the mouse button is released. This can be used to your advantage because of a quirk in the handling of the "cooldown" between blocks: the 0.25 second cooldown is reset when you release the mouse. Thus, with proper timing you can "click mine," increasing your overall digging throughput. The "thump" noise is helpful for gauging this: it plays exactly 5 times per second, starting as soon as you click. For example, mining Stone with an Iron Pickaxe takes 0.4 seconds, so there are two thumps plus a little extra time before the block breaks. It used to be possible to "switch mine" by switching targets right as the block broke to accomplish the same thing, but that no longer resets the cooldown. However, moving (walking/etc) while breaking does seem to reset the cooldown; tools enchanted with efficiency and a slight diagonal aim are the best way to use this.

Digging speed
The speed at which you dig is controlled by two factors: The block you are breaking, and the item you are currently wielding. Every block has a hardness, which determines the base amount of time to break that block if you hit it with your bare hands. The base time in seconds is the block's hardness multiplied by 1.5. The first adjustment to this is based on whether you can harvest the block with your current tool. If you cannot, then the base time is multiplied by 3.33.

Assuming that you can harvest the block, the next check is whether your tool helps speed digging for this block. By and large, Pickaxes speed up (and are required for) mining stone, Axes help chop wood, and Shovels dig dirt faster.

If your tool helps, then it increases digging speed by a constant multiplier, given in the following table:

Although Swords do not count as "helping" to harvest a block, they perform 1.5 times better (regardless of material) than bare hands or other items, although Swords take double durability loss when harvesting blocks. All swords have a speed multiplier of 15 against cobwebs. Shears have a multiplier of 15 against cobwebs and leaves, and 5 against wool.

Lastly, digging can be slowed if you are not on the ground. There is a 5x penalty (digging takes five times as long) if you are not standing on the ground while digging. There is also a 5x penalty to digging while in water. If you are swimming, (underwater and not walking on the bottom,) then the two combine for a whopping 25x penalty, making it very difficult to dig even with tools. However, if you cannot harvest with your current tool then only the original 3.33x penalty applies, and none of the other adjustments are made. This means that it is faster to punch stone while swimming than to use an Iron Pickaxe.

Blocks by hardness
The following table shows the time it takes to break each type of block. Values with a red background indicate that it cannot be harvested by that quality of tool. Note that some blocks, like Ice, don't drop anything even when they are "harvested"; these are marked with a yellow background. If there is no tool that helps speed up mining the block, the row will have a gray background.

History
As of Minecraft 1.0, it takes 4 minutes and 10 seconds to break obsidian using anything other than a diamond pick.

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