Netherrack

Netherrack is a rock-like block found in the Nether.

Obtaining
Netherrack can be mined only with a pickaxe.

Natural generation
Netherrack makes up most of the Nether's terrain, and also generates as part of ruined portals.

Nylium
Crimson or warped nylium transforms into netherrack if a solid, opaque block is directly above it. Netherrack can also be obtained by mining nylium without Silk Touch.

Nether portals
$$, netherrack generates as part of nether portals spawned floating.

Usage
When netherrack's top is lit on fire, the fire burns indefinitely.

bone meal on netherrack placed next to warped nylium or crimson nylium transforms the netherrack into more nylium.

Analyzing the netherrack in a material reducer, it turns out to be a volcanic silicate rock rich in mercury.

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