9-10mm is the size of these top drilled dancing coin pearl beads. They have some very nice luster. These freshwater coin pearls have some natural occurring lumps and bumps but who cares? The luster makes up for it. Freshwater coin pearl beads are created when a small flat disc shaped shell, instead of a round bead, is inserted into the oyster or more commonly these days, mussel. Most of these pearls are farmed in rivers, lakes or streams. The result is a a fabulous flat disc shape pearl. Our freshwater coin pearl beads are picked by their luster and size.