Block of Coal

The Block of Coal (also known as Coal Block) is a mineral block that can also be used as a fuel.

Obtaining
Blocks of coal can be mined using any pickaxe. If mined without a pickaxe, it will drop nothing.

Crafting
Blocks of coal can only be crafted with regular coal, not charcoal. It is crafted in the same way as other mineral blocks.

Usage
Blocks of coal are often used to store coal in a compact fashion, or otherwise used as a fairly cheap construction block.

Fuel
Blocks of coal can be used as fuel in a furnace. One block of coal smelts 80 items, which is more than the smelting time of the 9 coal items used to craft it. You will, however, need to actively monitor the smelting or use hoppers, as you can only place 64 items in the cooking slot.

Trivia

 * Cannot be crafted using charcoal due to logical issues with crafting and destroying.
 * Blocks of coal cannot be used as fuel for the minecart with furnace.
 * A full stack of coal blocks should smelt for 14.2 hours – over 42 Minecraft days.
 * That is a little over fifty times as many items as a lava bucket.
 * However, you will need 576 coal to do this.