Netherrack

Netherrack is a block that was added in the 0.6.0 update. It is spawned by the Nether Reactor which forms a large tower known as the Nether Spire out of it. After Update 0.12.1, it will only be obtainable through The Nether.

Smelting

 * 1 Netherrack + Any Fuel = 1 Nether Brick

Trivia

 * Making the Nether Reactor is currently the only way to obtain Netherrack in Overworld,
 * It will become obtainable from the Nether after the Update 0.12.1
 * Before the Nether Reactor was made of Netherrack, it was made of Obsidian in 0.5.0.
 * Netherrack is the only block which permanently stays on fire.
 * Netherrack cannot be obtained by hand despite being destroyed easily by hand.