Herkimer (Diamond/Crystal Quartz) & Oyster Pearl Necklace. 14kt Gold filled chain. This stunning & versatile short Necklace can be worn every day or for a special occasion. Wear it alone or with a longer Necklace for a layered LOOK. These amazing crystals get their nickname "diamond" quartz as they are similar in shape, clarity, and sparkle to real diamonds upon first look. This mineral owes its name to Herkimer County, New York, USA, the principal place where it is found.