.950 Sterling Silver Herkimer "Diamond": Shape, size, color and inclusions will be different on each Herkimer stones measure Approx. 20mm-25mm - 25mm - 30mm. Length of Pendant including Bale: Approx. 1.25" - 1 3/8". Handcrafted and artisan made All pieces are stamped or hallmarked for authenticity Herkimer Diamonds are beautiful quartz crystals of the magnificent works of nature, found to have a natural diamond-like shape. Each Herkimer Diamond is slightly different making your piece one-of-a-kind Herkimer diamonds are not actually diamonds, but double-terminated quartz crystals discovered within exposed outcrops of dolomite in and around Herkimer County, New York and the Mohawk River Valley. from Wikipedia