Netherrack

Netherrack is a frail stone block found abundantly in the Nether and in blobs below ruined portals. Fire lit on top of netherrack burns indefinitely.

Breaking
Netherrack can be obtained only with a pickaxe. It drops nothing if mined without one.

Netherrack can also be obtained by mining nylium with a pickaxe not enchanted with Silk Touch.

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

Netherrack generates as part of bridge and treasure room bastion remnants.

Post-generation
$$, netherrack generates as part of nether portals spawned floating. This is what makes netherrack renewable.

Crimson or warped nylium transforms into netherrack if a solid, opaque block is directly above it, or when it is covered by snow.

Usage
Netherrack is mostly used as a cheap building block. Because of its abundance and softness, it is often used to construct temporary structures that can be used for scaffolding, blockage, or other purposes.

When netherrack's top is lit on fire, the fire burns indefinitely. Unlike soul fire, this fire can spread.

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.

Note Blocks
Netherrack can be placed under note blocks to produce "bass drum" sounds.

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