Best website for Herkimer diamond information
A community project where Herkimer diamond scholars, collectors and miners share information.
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A free service to the public since 2008 with information not found anywhere else.
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This webpage contains photos of different minerals in contact with each other, or in relationships. Minerals that are the same, like two different types of dolomite, are shown on the mineral page of that specific mineral (click on Other Minerals above). The photos here are carefully selected to show evidence for which mineral came first. Sometimes, in the Herkimer district, this evidence is not easy to find. The purpose of this webpage is to provide photographic evidence for the General Mineral Sequence and to understand better the history of Herkimer diamonds.
More information is needed for this webpage - donations are welcomed.
Mineral Event Relationships - Which Came First?
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The photos here serve as clear examples showing one mineral episode growing on top of another different mineral.
Photo 1: Although dolomite and quartz are the two most common minerals in the Herkimer Mining District, it is difficult to find specimens showing a crystalization relationship between the two. In this specimen it appears as if the prismatic quartz grew after the dolomite. Specimen donated by Ted Smith of the Ace of Diamonds mine, Middleville, NY. Large dolomite in the center is 2 mm across. Photo Dr. D., 2008. If you visit the quartz sphere page you will clearly see a dolomite crystal inside one of the spheres.
Photo 2: Brilliant white dolomite from HBQ (2009) with needle second phase sulfides on top (see sulfide page). Often these are destroyed in the cleaning process. Also a first phase calcite on top of dolomite (top center). 15 mm across photo length.
W. David Hoisington, Ph.D.
More photos to come