Herkimer Diamonds are not true diamonds but are double-terminated quartz crystals found in Herkimer, New York. Incredibly, these gemstones are close to five hundred million years old. The crystals are naturally found with a diamond-like geometrical shape. Thus, the name recognition of “Herkimer Diamonds”.
A true diamond in rock is a rough appearing glass-like stone. The true diamond must be painstakingly cut by man to give it smooth faces and a geometrical shape. Herkimer Diamonds are naturally faceted, each having eighteen facets and 2 points. On the Moh's hardness scale, a true diamond scores a ten (one of the hardest elements) and a Herkimer Diamonds falls at a 7.5.
During the Precambrian period (1100 million years ago), New York State was covered by a shallow sea that was continuously being covered by calcium and magnesium carbonate sediments from the formation of the Adirondack Mountains. These sediments created dolomite bedrock, in which Herkimer Diamonds formed. Some Herkimer Diamonds have liquid inclusions--often as bubbles--of water, salt, and sometimes carbon dioxide. Other Herkimer Diamonds have solid inclusions of a black, coal-like substance called "anthraxolite."
Herkimer, New York
Size: 1.63 x 1.56 x .88 inches
Weight: 1.3 oz.