Obsidian

Obsidian is a deep purple block that was first released into that game at version 0.30. Obsidian is not found naturally in normally generated maps, except in Infdev.

Obsidian is available for use in creative mode. It is mostly used for making dark things, or the black lines of pixel art. In Survival mode, Obsidian was extremely tough to break and would drop one or two Cobblestone blocks when busted. Obsidian was not available anywhere in Indev. Obsidian could be created in Infdev; when pre-created water flows onto a pre-created lava spring. The obsidian never actually spawns with the chunk, but is created by the environment. Do not confuse this with cobblestone, which results when water collides with lava (not a lava spring). It takes 50 seconds to destroy with a non-pickaxe and 15 seconds to destroy with a diamond pickaxe. Obsidian can only be successfully mined with a diamond pickaxe. Obsidian is one of the most resistant materials to TNT, which only goes through one layer, which makes it one of the best material for protecting your valuables, along with cobblestone, mossy cobblestone, and possibly natural stone. Obsidian takes the longest to destroy without TNT.

Trivia

 * In one version of Infdev, obsidian blocks were used to mark the positions of the cardinal directions. This created two intersecting planes extending just above the surface of the solid material that surrounds them. This has since been removed.
 * Notch has mentioned he may require floating islands to require obsidian in the future:


 * Obsidian's data value is 49dec (31hex)