What Milwaukee is Made Of is Lake Effect's new series exploring the geological origins of Milwaukee’s building materials. How many million years ago did they form? Where in the world have they been? What brought them to Milwaukee?
In this episode, we look at the history of Milwaukee's most famous building material: Cream City brick.
Cream City brick's story starts around 25,000 years ago during the Ice Age, when glaciers deposited clay, rocks, and other material in the Milwaukee area. Water from glacial melt and Lake Michigan brought additional sediment into the mix. By the time it was used as a building material, the clay that would become the brick was over 100 feet thick in some areas.
Geologist and author Raymond Wiggers said that typically bricks are red or brown because the clay they come from contains iron, which turns red when heated in a kiln. But Milwaukee's local bedrock, combined with the iron, gave the brick its unique color.
"Our local clays... have a huge amount of calcium and magnesium," Wiggers said. "It turns out when you burn that with the iron, especially if you pump up the temperature a little higher, which Milwaukee brickmakers generally did, you get this beautiful, weird pale-yellow color."
Cream City Brick as a building material
The brick's distinctive color gave the city its "Cream City" nickname and was used in buildings all over the city before falling out of favor in the early 20th century due to cost and changing aesthetic tastes.
But one building carries a special connection to the brick: the J.L. Burnham Block. Built in 1875, the building features three stories of Cream City brick from a brickyard owned by one of the brick's earliest purveyors: John Burnham. The Burnham family had one of the area's largest brickmaking operations in the 19th century before splitting the business.
Wiggers said the building's original use is comparable to an early version of a "mini strip mall."
"It was a multi-use commercial building, so whatever Burnham could get people to use it for, he would let them use it for that," Wiggers said. "It had a dance hall or meeting hall up above and a commercial space down below."
Raymond Wiggers is the author of "Milwaukee in Stone and Clay," a book about Milwaukee architectural geology.
