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Saturdays attempt to identify rocks in the Great Lakes: Jacobsville Sandstone

Jacobsville Sandstone, also known as Lake Superior Sandstone, was formed approximately 550 million years ago. The history about the stone is really interesting. But we will get to that in a minute. Jacobsville sandstone is a combination of quartz-rich to feldspar rich sandstone. Which directly leads to the colors and patterns of the stone. The sandstone is typically red due to iron oxides found in the matrix. It can come with white streaks, or spots from bleaching. These are fairly easy to spot on the beach. Just like any other stone, each one has their own little pattern or fingerprint. On the mohs hardeness scale, it ranks out between 6 and 7. I have not done a whole lot with tumbling or polishing. Im pretty sure it wont end up well. I have added some pictures for examples. Some of the history of the stone began in a town named, you guessed it, Jacobsville. The town started back in 1887 as a fishing village. Located near the mouth of the Portage river, the Jacobsville formation actually was an east-west division of the Keweenaw Peninsula. The commercial quarrying of the stone went from 1880 to just into the 1890's. The sandstone was mined for the building of blast furnaces as well as other construction projects around the Great Lakes. It was broken off in huge chunks and blocks to be shipped to their specific destinations. It can be found all across the Great lakes due to its transportation and uses.

I found the Wiki information interesting. If you are interested ion learning more its worth the click. Have an Awesome Day!

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