There are a limited number of commercially available diamond mines currently operating in the world, with the 50 largest mines accounting for approximately 90% of global supply. Diamonds are also mined alluvially over disperse areas, where diamonds have been eroded out of the ground, deposited, and concentrated by water or weather action.
The largest quarry in the United States is in Miami, Florida. It is owned by the Rinker Materials Corporation. The limestone quarry, which includes a cement plant, supplies building materials to engineers all over the world.