Hellstone

Hellstone is an ore that can be found in The Underworld. Mining it requires at least a Nightmare/Deathbringer Pickaxe, and it cannot be mined with in pre-Hardmode. Hellstone in the Underworld emits a faint glow and releases a half-tile of lava when mined. Hellstone tools are among the most powerful that can be acquired in pre-Hardmode, rivaled only by three tools that can be caught from fishing, the Sawtooth Shark, Rockfish, and Reaver Shark.

Hellstone inflicts the Burning debuff on players who touch it. Items that protect the player from the debuff (including the Obsidian Skull and its derivatives) will allow players to touch it without incurring fire damage. NPCs and enemies do not receive damage from Hellstone.

Tips

 * Lava can be farmed by repeatedly mining and placing Hellstone in The Underworld.
 * Placing gravity-affected blocks such as Sand Blocks on top of Hellstone before mining will keep the Hellstone from inflicting damage.
 * Use an Obsidian Skin Potion to become immune to the lava that generates when hellstone is mined.

Trivia

 * Hellstone, Meteorite, Luminite, and Obsidian are the only ores that do not have "ore" in the name.
 * Hellstone is the only ore in the game whose bar requires a material in addition to its ore to smelt.
 * In the real world, is sometimes called "Hellstone".
 * In 1.0, Hellstone was considered an endgame ore.
 * Hellstone has a special immunity to lava in the code, despite its rarity of stopping that anyway.
 * This is because before update 1.1, it had a rarity of, so it needed that code to prevent it from burning.