Herkimer Diamonds are beautiful double terminated Quartz crystals. They are considered to be a "Master Crystal" in the metaphysical community. Herkimer diamonds are known to be extremely high vibrational and enhance the energy of other stones and crystals around them.
The Herkimer Diamond Quartz for sale here are from Herkimer/Fonda, NY. They were mined in the 1980's by Robert Sanwald.