Glowstone

Glowstone (formerly known as Lightstone, Brittle Gold, Brightstone, Australium or Brimstone) is a golden block that glows indefinitely. This block can only be found in The Nether. It grows on the undersides of blocks, commonly near lava, and forms unusual coral-like stalactites. Glowstone has a luminance of 15.



Breaking this block drops Glowstone dust. Glowstone has no crafting use; however, it does have a practical use. Unlike torches, it isn't destroyed by water and continues to emit light even when submerged. In this respect, it's a functional and easily applied underwater light. Additionally, the block is a natural source of heat and will melt nearby snow and ice.

Glowstone does not require a tool to be harvested, and makes the same sound as glass when shattered. Swords can be used to break Glowstone at a faster pace, with the cost of two uses.

Trivia
Glowstone could potentially be an item requirement to craft a lantern, as it also provides an infinite source of light. This would also make lanterns relatively inaccessible and a risky item to get, as has been hinted at by Notch.