Herkimer Diamonds and Little Falls Diamonds are quartz diamonds that were formed about 500 million years ago in the dolomitic limestone ( Little Falls Dolostone) that lines the Mohawk Valley. One theory of how the crystals were formed is that an ancient seabed once covered this area, and a die-off created the proper conditions for these crystals to form. Other evidence of a seabed that once was can be seen in the stramatolite (or cryptozoon) fossils found within the Little Falls Dolostone.
Herkimer Diamonds were first discovered in Little Falls NY. They are unique in that they come out of the earth as a double terminated crystal with 18 naturally formed faces. This gives them the appearance of being cut or “faceted”. They are also known to be the world’s clearest quartz. True Herkimer Diamonds are only found in Herkimer County, NY.