These sparkling crystals look like real diamonds to the untrained eye. Since these unique crystals are found in Herkimer County, named after the Revolutionary War General Nicholas Herkimer, the crystals became known as "Herkimer Diamonds". These gemstones are brilliant, water clear quartz crystals composed of silicon dioxide and are hard enough to scratch glass. They are of a hexagonal structure and doubly terminated (points on both ends). This is a special collection of jewelry made from these special gemstones in both sterling silver and gold filled metals.