Herkimer Diamonds is a name given to double terminated Quartz crystals found in the Herkimer County area of New York. Workmen discovered them while cutting into exposed Dolostone in Herkimer County and the Mohawk River Valley in the late 1800s. These amazingly clear Quartz crystals have 18 facets, six sides along with the double termination. Geologists theorize the Quartz crystals formed slowly in vugs or small cavities in the Dolostone rock outcroppings. Herkimer type Quartz crystals have also been found in Tibet and Afghanistan among other places.