Made from slag, a byproduct from a copper smelting refinery. Copper grit is less expensive than steel grit and works as effectively because the grits have pointed edges and contain over 30 % iron. Can be collected and reused. The size of the grit is 0.5 - 4.5 mm in mesh and it is packaged in quantities of 30 kgs in durable paper bags. Sold by metric ton.