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Mineraology

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Limonite or Brown Klematite iron ore is found a mile or more east from Mineral Point associated with copper ore. Fragments of this ore have also been found on the ridges near Rock river, and on Sugar river in Green county but nothing is known of the quantity of ore to be found at these places.

Iron Pyrites or [Iron] Sulphuret of Iron is found abundantly in the limestone along the shore of Lake Michigan and in rolled masses on the beach. Fine specimens are dug from the hard blue and yellow clay forming the lake shore at Milwaukee. It is associated with the copper ore at Mineral Point in considerable quantities. The people of Wisconsin like those of many other countries have been deceived by the bright golden or bronze yellow color of this almost worthless mineral into the belief that they had made a valuable discovery. It is used in the manufacture of coppers and sulphuric acid (oil of vitriol) [but] & may be found here in sufficient quantities to be of value for these purposes.

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