Herkimer Diamonds

Herkimer Diamonds are totally natural formations of sparkling double-terminated, exceptionally hard, quartz crystals which are found in Herkimer County, New York. These gemstones formed about five hundred million years ago. Herkimer crystals are the magnificent artistic results of Mother Nature’s work. They are found in vugs or pockets in the host limestone rock (often called dolorock or dolomite). They rival any stone that has been precision cut by man. Since they naturally have a diamond-like geometrical shape, they were given the name “Herkimer Diamonds”

A void which contains a single Herkimer diamond is referred to as a vug. If multiple diamonds are found in the void it is called a pocket. A black coal like lining of Anthraxolite often occurs inside the vugs and pockets where Herkimer Diamonds are formed, giving the vugs or pockets a solid black appearance. Some crystals are found with black inclusions. The locality of the Anthraxolite both inside and outside of the crystal, suggests it was present before, during, and after the crystals were forming. There are many versions and legends of how these majestic gemstones formed.

The double terminated Herkimer Diamond silica crystals are very rare in nature and it is suggested that these crystals were able to form without having been attached to the host rock matrix during the critical growth period. This occurred because silica has no attraction to the dolomite rock and avoids attachment to it. The majority of quartz crystals form in rock rich in silica and this usually results in the quartz forming with at least one end of it attached to the host rock.

The perfect Herkimer Diamonds have eighteen faces. Six triangular faces form the termination points on each end of the crystal with six square or rectangular center faces connecting the ends. This results in a diamond shape. Deviation in the face plane on a Herkimer Diamond has been measured at less than two thousandths of an inch. Man has to work with great precision to even come close to Mother Nature’s perfect formation of the Herkimer Diamond.