These are tiny – less than an inch long – and they are not diamonds at all, but a type of double-pointed clear quartz.
The name ‘Herkimer‘ comes from Herkimer County in New York State, where the crystals occur in outcrops of dolomite. A couple of mines are open as visitor attractions, allowing people to hire tools and do some prospecting for their own crystals.
Herkimer diamonds are thought to have been created about 300 million years ago, when liquid seeped into cavities in the dolostone bedrock. These cavities are thought to have been left by decaying plants because they are often lined with anthraxolite, a hydrocarbon which is derived from organic material.
The crystals always have 18 facets, and they are double-terminated because they do not have an affinity with their host bedrock, so they will not attach to it. Their silica-rich composition gives them a greater clarity than ordinary rock crystal.
Little pockets known as inclusions occur within the clear quartz. The blackish inclusions are anthraxolite, while the yellow ones are petroleum. The petroleum pockets are still liquid, and when you study them closely you can see tiny bubbles of air trapped inside.
Looking through a magnifying glass, I can get some of these air bubbles to move when I tilt the stone – it’s like playing with a spirit level!
Properties of Herkimer diamonds
The native American Indians called Herkimer diamonds ‘spirit stones’. In crystal healing, they are used as an amplifier of energy, and are said to boost clairvoyance. They will help you connect with your guardian angels and will allow two or more people to stay attuned to each other, even when they are physically apart.
Herkimer diamonds are believed to promote prosperity and a positive outlook on life. When placed in the workplace they can clear electromagnetic pollution, and if you are doing research they will help to store knowledge. I’m not exactly sure how they can do this, but I’m putting one on my desk right now!
Photos copyright © Jo Woolf