Herkimer Diamonds

These beautiful, doubly-terminated quartz crystals have already been faceted by nature. The bedrock in which they are found began forming approximately one-half billion years ago in a shallow Cambrian sea that lapped against the southern shores of the ancestral Adirondack Mountains. The limy sediments (calcium magnesium carbonate) which had accumulated beneath the sea were gradually compacted under the weight of thousands of feet of additional sediments, forming the rock strata known as Little Falls Dolostone. While still beneath the sea, water seeped through the pores of the rock, creating “vugs” by dissolving part of the rock. Millions of years later, silica rich water filled these vugs and eventually evaporated, leaving the silica to form quartz crystals.