Granite is a grey stone that fills the
              majority of underground world and make mountains stand 
              tall.Sometimes contains veins of coal, and, often deeper,
              iron. When harvested, turns into cobblestone, which can
              be smelted back into pure granite. -In-Game Description
Texture: Stone
Tool: Pickaxeempty2
Block ID: 3
Transparency: No
Blocks fluids: Yes
Furnace fuel: No

Granite was in the game since it was released, but before Aplha 1.3 it was called stone. It is also known as smooth stone or natural stone. It is found under dirt, sandstone or water. It rarely occurs on the surface. When mined, drops cobblestone, which is the most common building material in the game. As of Alpha 1.3, it can be converted back to cobblestone by smelting it in a furnace There are no crafting recipes with granite. It is the most common naturally generated block in the game, since it can be found anywhere from the surface to bedrock.

Mining Times
Hand: 10 secs
Wooden Pickaxe: 2.5 secs
Stone Pickaxe: 1.66 secs
Iron Pickaxe: 1.25 secs