Cobblestone, the cracked product of mined Stone, is one of the most common Blocks in Minecraft. It is found either by mining ordinary stone or in dungeons that have been generated by the game, along with Moss Stone. It can also be found in strongholds, villages, and jungle temples. Cobblestone doesn't have physics applied to it, so it makes a very good construction material and is used to craft a Furnace. It can be smelted in a furnace to turn it back into Stone. Once Cobblestone is smelted, it becomes considerably weaker in blast resistance than it was before. Cobblestone can be easily obtained by mining downwards through the top few layers of Dirt.
Cobblestone is mostly used for creating Furnaces and building shelters. Cobblestone can also be used for Tools, such as Pickaxes, Axes, Shovels, etc. Cobblestone is also used for some weapons, such as Swords. Cobblestone is also very blast resistant, making it one of the easiest blast-resistant materials to obtain.
When flowing Water and flowing Lava meet, they create Cobblestone, allowing Players an infinite supply of Cobblestone, assuming the Lava and Water source blocks aren't blocked off or removed. However, if lava flows on top of water, or water on top of stationary lava, stone or obsidian is formed, respectively, instead of cobblestone.
Cobblestone is used in 17 different crafting recipes.
Cobblestone is resistant to Ghast fireballs, making it useful for guarding Portals.
Cobblestone was actually introduced before Stone was.
In past versions, Cobblestone had a lighter texture to it.
In the game files, cobblestone is called item.tile.stonebrick
Cobblestone is one of the few blocks obtained by mining a different block, Stone, in this case.