Herkimer diamond quartz on sterling silver.  3/4" long from top of wire to bottom of quartz.  Herkimers are approx 3/8" wide.

A double-terminated quartz that makes it have multiple “faces” that join in diamond-like patterns. Herkimer diamonds are rated seven on a 10-point hardness scale as compared to the diamond, which rates 10.  Geologists believe Herkimer diamonds began forming inside crevices in a shallow sea almost a half a billion years ago.