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Sulphate of Barytes or Heavy spar is said to occur in narrow seams in boulders or fragments of limestone on the Wisconsin river.

Calcareous spar, is abundant at the Lead Mineral where it is called "Tiff". It occurs in the limestone on the Neenah and various other places; also at the Grand Portage on the St. Louis river in perfectly transparent [rhom...illegible] exhibiting the phenomena of double refeaction.

Marble, or limestone having the requisite qualities for being polished and hence useful for many kinds of ornamental work, is found in various places. Very beautiful grave stones are manufactured from stone quarried in the town of [Prairieville] Genesee in Milwaukee county. The "Blue Limestone" in some places makes a very beautiful marble, the shells and corals giving it a peculiarly fine character-hence called "shell marble."