Most sandpaper today is made from synthetic minerals, but there's still a place for garnet, a relatively soft natural mineral with a distinctive orange color. The sharp edges of garnet particles round over slightly to form a ?U? shape while sanding. It's well suited for sanding softwoods. Because scratch marks are not as sharp and deep as they would be with a different kind of abrasive, the finish surface seems especially smooth. Garnet is typically sold in sheet form with a paper backing. It's designed for dry sanding by hand or with a light power tool, like an orbital block sander. 3M sells garnet sheets in grades P100, P120 and P150. In December 2004, a 9 in. by 11 in. sheet of 100-grit paper cost about 32 cents.
Supplier: 3M
