How to make a cobblestone generator in Minecraft
A cobblestone generator gives you endless Cobblestone from one Lava Bucket and one Water Bucket.

A Water Bucket carries one water source that you can place anywhere.
It cannot be crafted; it can be found in chests.
Fill an empty Bucket from any water source. Placing it creates a source block: two sources next to each other make an infinite water supply. Players use it to break a long fall, to put out fire, to make obsidian over lava and to fill cauldrons.
In the Nether the water instantly evaporates. A water bucket also catches fish, axolotls and tadpoles into mob buckets.
This item has no crafting recipe.
A cobblestone generator gives you endless Cobblestone from one Lava Bucket and one Water Bucket.
Pour one Water Bucket at each end of the trench.
put it in a water source, or place it on land and empty a Water Bucket on it.
It can be found as loot in Trial Chambers and Village. Bought by Wandering Trader.
It places water for farms, falls, fire and obsidian.
No: only one per inventory slot.