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Found this stone or rock while moving. Unusal looking. Thanks for time and helping solve a mystery.

Hi John,
Looks like you have a nice example of a sedimentary rock pebble.  A sedimentary rock is one that's made of other rocks that have been broken down by erosion.  "Sand" is small pieces of quartz that have been broken down from larger pieces.  Heat them up, and add some pressure and you make a rock.  You can also make a solution of minerals and water which can act like a glue to hold the grains together.
In any case; big rocks broken down, small pieces gather together (by wind or water, but that's another story), and all are lithified by some process.
Often there are layers in the rock, just like yours.  From the image your's looks like a sandstone.
Here's a web site that has some good pics of sedimentary pebbles.  You'll have to scroll down pretty far to see some that look like your rock.

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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