Dark Stone

Its like normal stone, it generates below snow in the mountain update. It could be a little more compressed so that you can use a table to turn 9 blocks of normal stone into dark stone. Mining dark stone will give dark cobblestone. It can make normal furnaces but they could have darker color. Dark stone will help builders a lot to have a little lighter color than blackstone, and having stone bricks version of dark stone could help make cracks in large walls of normal stone bricks.