Mycelium

Mycelium is also a game feature of Minecraft.
More information can be found on the Minecraft Wiki at Mycelium..

Mycelium
Item Details
Type	Block

Mycelium is a particularly rare variant of dirt that is found naturally only in mushroom fields biomes. It has a particle effect that resembles tiny spores being released constantly from the surface.

For further information, please refer to the Vanilla Minecraft block.