Dr. C’s Blog about Exploring the Herkimer Mining District
The Best Site on the Internet for Herkimer Diamond Information - A Collaborative Project.
Every year something new is discovered within the Herkimer Mining District. You can find these under New Discoveries
The information, and photography, on this website is copyright protected by W. David Hoisington, Ph. D. unless another author/photographer is cited.
Welcome to the New Herkimer Diamond Story!
Return often and follow this developing story. Refresh your browser (right click) to see new updates
The blog entries are aimed at presenting non technical discussions of the collaborative work being done on expanding the story of how Herkimer diamonds were made. At the start of each year the blog page will begin fresh and the previous year’s blog entries put on a separate archive webpage.
Thanks to someone who has contributed much over the last year
New Discovery Posted - The Quartz Rhombic Cast - 03/07/2018
See the New Discoveries page… The photo on the right is of the quartz rhombic cast. This quartz rhombic cast is an inclusion within a Herkimer diamond and one located close to the wall rock contact. If you have a collection of Herkimer diamonds then you probably have one of these quartz rhombic casts in your collection. The explanation of how these were formed can be found in the slides on the Hydrothermal and Vertical Flow page (slides 22 - 26). These are quartz casts made as the dolomite crystal was being altered, disolved, by the hydrothermal fluids.The Hydrothermal and Vertical flow page also includes new photos showing how the pocket wall rock has been hydrothermally altered. Most exciting, in this authors humble opinion, are the quartz micro-veins. These are very difficult to see in the field, and difficult to photograph in the lab. Most are transparent and very small. Occassionally one will have a bit of hydrocarbon in it and thus provide enough contrast for a good photo. It is proposed here that the Herkimer diamond pocket wall rock has many of these quartz micro-veins and this accounts for the toughness of the wall rock, as reported by those with the experience of trying to drill through it, cut it with a diamond blade, or smash it with a sledge hammer.
New Photo Documentation Added - Hydrothermal and Vertical Flow - 03/07/2018