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Marcasite Decomposition

Posted by Brian Kulwik  
Brian Kulwik March 02, 2012 10:36PM
I have some specimens of what I believe to be marcasite, in many forms--concretions, crystals, and stalactites--that I found in one locality. Some of these are undergoing decomposition, forming into white crystals and falling apart, especially the stalactites. I was wondering if anyone knew why some of these were decomposing and others are not, and if there is any way to stop them. Once they start to get the white crystals, it is about six months before they start falling apart and one to two years before they become a pile of white powder...

Also, does anyone know if these are of any value (the ones that are not falling apart...) I have bags full of concretions, marcasite??? stalactites, and marcasite/pyrite crystals, and I was wondering if these would be worth my time to try to sell. If so, where would I go about doing this?

Thank you very much.
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Vik Vanrusselt March 03, 2012 12:49AM

check this out, maybe it'll help (pyrite/marcasite decay in fossils):

D Mike Reinke March 03, 2012 04:58AM

Have you seen the long thread "pyrite disease" from a few months back. Very informative.

Brian Kulwik March 05, 2012 04:05AM
Thank you guys for the helpful links!
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