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I'm wondering what the rock on the left is, I believe it may be a quartz rock, it's really fine and hard.  To compare on the right there is what I belive is a quartz crystal but not so fine or hard.

Hi Petes,
It's a bit hard to tell from the pic, but I think you are right. It looks very fine grained and, more importantly, I think I can see a light reflecting on the surface. If there is, and without more information or seeing it directly, I'd have to agree the rock is probably quartz.

Hope this helps.


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C. Robert Reszka, Jr.


I can answer any general geology question (rocks, minerals, stratigraphy, geomorphology etc.). My expertise is in the geology of the Michigan Basin, PreCambrian, Paleozoic and Recent. I can answer questions concerning mining and petroleum exploration and production and the laws concerning those activities. I can also answer questions concerning stratigraphy of the Michigan Basin. I will also answer questions about mineral and rock collecting in the Basin. I won`t be able to answer many specific questions on hydrology, geophysics or geochemistry. I may be able to answer very general questions in those venues.


I have been working for the State of Michigan for 36 years as a Geologist and a Resource Analyst. I have experience with Subsurface Geology and Petroleum Geology, mining in Michigan, and Sand Dune Mining and Protection issues.

Michigan Basin Geological Society

Decade of North American Geology.
Bedrock Geology of Michigan

BS Wayne State University

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