Over 500 million years ago, grain by grain , rock was eroded and washed down into the lowlands of what is now Lake Superior. Sometimes it was laid down slowly in clay or into sand of a lakebed or from rivers swollen by storm run-off. There is no record of life existing in these sediments, but they hold evidence of rain, and of an atmosphere with enough oxygen to form the iron oxides that coat and cement together each quartz grain with the rust color characteristic of brownstone. These layers of sediment were laid down year after year.
Today, hints of this past can be seen along the southern shore of Lake Superior in a narrow belt six to eight miles along Chequamegon Bay and the South Shore to Port Wing and on several of the Apostle Islands, this is called the Keweenaw strata. The names of these sedimentary rock formations come from their locations: the Fond du Lac formation in Minnesota, The Bayfield or Lake Superior sandstones (brownstone) along the south shore in Wisconsin and the Jacobsville sandstone in the Upper Peninsula of Michigan. The hardness of the brownstone, and thus suitability for building, is determined by how fast or slow the stone can be sawed. For example, sandstone from a quarry in Michigan sawed at a rate of 28 inches per hour. The Lake Superior sandstone sawed at a rate of 4 inches per hour!
The quarrying of brownstone became an important local industry in the late 1800's with several quarries operating between Washburn and Bayfield along the sandstone outcrops. At the height of the industry, seven quarries were operating in Bayfield County. One such quarry can be seen just off of Highway 13 (see waypoint). The first brownstone was quarried on Basswood Island in 1869 . By 1871 brownstone was being shipped down the lakes to Chicago to rebuild that city after its devastating fire. Lake vessels, docked alongside many of the quarries, loaded and shipped cargoes of up to 600 tons of undressed stone.
In 1892 Frederick Prentice, president of the Prentice Brownstone Co., offered to supply a huge brownstone monolith for the Wisconsin Exhibit at the 1893 World’s Fair in Chicago. He proposed to furnish this impressive one piece structure at a size of 110 feet high, 10 feet wide at the base and coming to an apex of 2.5 feet, which, according to Mr. Prentice, would eclipse the Egyptian Obelisk that measured 105 feet, 7 inches high. The Houghton quarry was selected because it had the best brownstone for the purpose, i.e., free from clay pockets, tints and streaks. Unfortunately, the cut stone never left the quarry because it became too expensive. Mr. Prentice withdrew his offer and the huge stone was cut and reshaped for use in other buildings. In 1893 Prentice cut 750,000 cubic feet of sandstone and by 1903 the industry all but died, having been replaced by concrete and other building materials.
The building in front of you is one of the finest examples of a brownstone building anywhere. It was built in 1890 as a bank and now houses the Washburn Historical Society and Museum. Go inside and further examine some of the history related to the industry.
*** Washburn Brownstone Building Tour***
So from the bosom of darkness our days come roaring and gleaming,
Chafe and break into foam, sink into darkness again.
But on the shores of Time each leaves some trace of its passage,
Though the succeeding wave washes it out from the sand.
-Henry Wadsworth Longfellow
TO LOG THIS CACHE:
1) How tall is this brownstone object?
2) Upon close examination of the brownstone, do you see any quartz grains without any of the iron oxide coating?
3) Who erected this particular brownstone object?
To log this cache e-mail me the answer HERE.
Dott, R.H. and J.W. Attig (2004). Roadside Geology of Wisconsin. 400 p.
Washburn Historical Society and Museum