Montello Granite

The Montello Granite which is found in mounds located in Marquette County, is dated at about 1760 million years. It is named after the city of Montello, which has an old quarry as part of a downtown park. The Montello Granite is a dense, fine grained rock uniform throughout the quarry. Over one half of the rock is composed of feldspar, while more than four-fifths of the remainder is quartz. The little bit that is left is composed of magnetite, hematite, chlorite, hornblende, and muscovite. This mineral composition is what gives the Montello Granite such great strength and durability. The Montello Granite has a red color, but two variations. One shade of red is a bright cherry red while the other is more of a grayish red. Along the joints you will find the granite stained with a yellowish-brown iron oxide, along with some black and white streaks mixed in, in different directions. These dark streaks are a result of the greenstone magma, and the white streaks are small veins of secondary quartz. These veins, when present, make the uniformity of color which is one of the most important qualities of monumental stone. The Montello Granite also has strength and durability, which is important for monumental stone, but it also makes it hard to quarry and polish. You will find it used in cemeteries of Illinois, Indiana, Ohio, Pennsylvania, Michigan, Iowa, and Wisconsin. Montello Granites have been used for national monuments such as the General Custer Monument, monuments to Wisconsin Soldiers at Gettysburg, Pennsylvania and Chickamauga, Tennessee, and the sarcophagus for General and Mrs. U.S. Grant at Riverside Park, New York. Montello Granite is also found in many important buildings such as the Herald building in Chicago.