Stonecutter

Stonecutter is a block used to craft stone related items $$, but $$ it is unused and can only be used as a decoration.

Natural generation
Stonecutters can generate inside mason houses in villages.

New Nintendo 3DS Edition
Stonecutters are only available from the creative inventory.

Bedrock Edition
The stonecutter is only available via Creative mode. It is unobtainable in Survival mode and only exists in survival worlds where one existed prior to Pocket Edition Alpha 0.13.0. However, it can be used as a decorative block when obtained from the creative mode inventory. In Bedrock 1.10 however the old stonecutter will probably be removed because if not there would be two blocks with the same ID. But you will be able to get it if it was placed in a world in an older version.

Usage
The stonecutter can be used as a cheaper alternative to the crafting table to craft most stone related blocks, as all of its recipes only require one ingredient each.

Nether brick fences cannot be made here.

Change profession
If a village has a stonecutter and there's no stone mason villager, any nearby villager who hasn't chosen a work station has a chance to change their profession to stone mason.

Trivia

 * In Pocket Edition, stonecutters were added due to a lack of space in the MATTIS crafting screen.
 * In New Nintendo 3DS Edition, the stonecutter has always been a purely decorative block.