Tutorials/Amethyst farming

 farming is the renewable way of obtaining amethyst shards, as well as small, medium, large amethyst buds and amethyst clusters. Amethyst shards are used to craft amethyst blocks for decoration, Tinted Glass (useful for mob farms), and , and to breed Allays.

A few key points

 * Amethyst clusters will only drop 2 shards if harvested by a piston, however if you harvest it with a Fortune 3 pickaxe it can give you either 8, 12 or 16 shards per cluster mined. That means that unlike many farmable mobs, items and blocks, farming amethyst manually can yield more amethyst than if you farm it automatically.
 * All the stages of amethyst buds and clusters will only grow and mature to the next stage if planted on a budding amethyst block. Budding amethyst blocks can produce new amethyst shards, but can only do so if a side is unobstructed and does not have any pending amethyst buds growing, and, like most blocks, it has 6 sides.
 * Budding amethyst blocks itself are non-obtainable blocks, like monster spawners, which means that they won't drop if you mine them, no matter what tool and which enchantments you use. It can only generate in amethyst geodes, so if you want to farm them, you need to find an amethyst geode, and turn that area into the farm.
 * A block of budding amethyst has a 20% chance every random game tick to produce a small amethyst bud if there is a free slot on a side, however amethyst buds themselves take about 7 Minecraft days to mature, though this can be longer or shorter due to the nature of random number generation in the Random Ticks and the Chance to Grow. Amethyst geodes are normally in fairly remote locations, especially if you are playing on a world you created before 1.17, so it is recommended you locate a geode near a farm you AFK at since the growth is restricted by the 128 block range from the player imposed by random ticks.

Manual farming
Manual farming amethyst is much more efficient than automatic, unlike with most farmable items. However, just going to each bud and mining it is fairly tedious, so here are a few methods that will help you in your Minecraft world. Please note that for all these methods you will need to dig out all the blocks within a certain radius of the geode that is not a budding amethyst block, including calcite, smooth basalt and stone, as well as blocking off all caves. You can use a nether portal system to enter and exit the area.

Scaffolding method
What you will need:
 * Some blocks
 * Some scaffolding and ladders
 * Some torches for light

This method is the most simple of all. You need to make a few floors using the blocks, and make each one accessible by using ladders. Then you will need to be able to access all the budding amethyst using scaffolding, but make sure that the scaffolding is not obstructing any sides of the budding amethyst. Also make sure to light up each floor.

Float method
This method works best in an amethyst geode which is under an ocean, because you will do much less mining, clearing out and placing all the water, but this is an extremely easy and efficient method that can also work in an underground geode if you are willing to do all the tedious work required. This will not disrupt the growth of amethyst, since amethyst buds and clusters can be waterlogged and grow in water source blocks and are not affected by it.

What you will need:
 * Some water buckets or several stacks of ice
 * Some conduits and enough prismarine to make all of max-level
 * Some blocks or glass
 * If you are building it in an ocean biome, some light sources that work well underwater, such as sea lanterns, glowstone or jack-o-lanterns are required. This is needed to prevent drowned from spawning. If you are not building this in an ocean biome, you will not need them, since you can already see clearly underwater with the conduit power.
 * Optionally at least 1 soul sand and 1 magma block for a bubble elevator
 * Optionally a Haste 2 beacon if you are digging out a large area

What you need to do is dig out a large area if you are underground, and mine all of the blocks around the geode that are not budding amethyst. If you are over the ocean then you will need to mine out all of the blocks around the geode that are not budding amethyst as well, and wall off the area from the rest of the ocean using blocks or glass (in an underground environment you will need to block off all the caves). This is recommended if you don't want drowned to enter and the items to scatter when they float. Then you will need to flood the entire area with water (all blocks have to be water sources otherwise this method won't work, so do it layer by layer), and spread out the conduits so that you are able to get the conduit effect in every single water block in the whole area. If you are in an ocean biome then you will also need to light up the water. In one corner you can also place a soul sand block next to a magma block to make a bubble elevator and an even easier way to get to the surface and floor. To harvest all you need to do is swim down to the geode and harvest all the mature amethyst clusters. The drops will float to the surface of the water, so collecting the items is simple. The only downside to this farm other than the resources it needs is that the items can despawn if you don't pick them up after 5 minutes.

Hole method
This method is extremely efficient, and you won't need to worry about items despawning.

What you will need:
 * Some blocks
 * Some water
 * Some torches
 * Resources to make a collection system

First you will need to build 1 floor, but make sure that it is at least 5 blocks over the highest block of amethyst. Then you will need to make a hole in the floor where a block of budding amethyst is directly below it and repeat that until directly above every block of budding amethyst there is a hole. You can now place a water bucket in each hole. This will allow you to access the budding amethyst without blocking any over it, so that the collection system can pick it up. Now you will need to build the collection system itself on the bottom floor which is under the blocks of amethyst (you will have needed to dug out the area first). You can do the system however you want, with water flowing for example, which pushes the amethyst shards over a hopper minecart system which collects it and funnels it into a chest. The last step is to light up the area. To use the farm you need to wait for the amethyst to grow, and to harvest you need to swim down each hole and harvest all the amethyst there. If you drop any amethyst it will be collected, so despawning is not a problem.

Automatic farming
There are a few approaches to making an automatic amethyst farm. All approaches require a timer of 167 minutes, the statistically optimal period based on the random tick rate. (As Redstone Comparator does not read the growth stage, the only way to know the stage is an Observer linked to a counting circuit. There's no chance for such a circuit to fit in a limited space, so probabilistic pushing is the best option.)
 * The simplest is to have a piston for each side pushing shards into a hopper. For an example design, see Gecko's video.
 * The ultimate efficiency in Amethyst farming comes from a flying machine system clearing every bud. Designing such a system is very difficult, however. A mod called "geodesy" is designed to help with calculating block placement for the flying machine.

Videos
Manual:

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