Cream Brick Churches of Wisconsin

St Stanislaus, built in 1873. 
Milwaukee.

King Solomon Baptist Church (formerly Evangelische Dreieinigkeits Kirche), built in 1892. Milwaukee

Bethel Baptist Church (formerly Evangelical Lutheran Zions Kirche), built in 1883.         Milwaukee

St Boniface Roman Catholic Curch, built in 1881.  Manitowoc.

Cream City Brick Glazed Coffee Mugs

I recently got 3 pieces back from the kiln with one of the cream city brick glazes I developed. I was very pleased with the results. I used a red clay, and the overall color was much darker. I really like the way it looks, but it did come out darker than the test samples on the gray clay. The lighter clay glazes matched the color of the brick very closely, so in terms of capturing the essence of the brick I think I prefer them. The iron in the red clay interacts with the glaze, and is pulled into it during the firing process, resulting in the darker glaze.It did have a nice texture and a rustic look that matched the bricks well.

In the second mug, I found that the glaze goes on nicely when applied very thick, and actually looks a lot better than the thin coating. I really liked the way the cream city glaze interacted with the white glaze.

Fox Music

Fox Music is located at 100 E Main St, Watertown, Wisconsin. This is a store I spent significant time in as a kid, although it was in a different location then. In addition to being an interesting place to shop for old records and antiques, the current location is an excellent example of cream brick architecture from the turn of the century.



According to the Watertown Historic Society, it was originally two buildings built in 1890 and later joined. The original buildings were the Clara Weiss Millinery Store and the Merchants National Bank. Clara Weiss produced women's hats until the 1920s and was well know in the city for her lavish parties to celebrate the anniversary of her divorce. Any German speakers know what that word means?

Fox Music is a sprawling store that takes up two floors of the entire building. You can wander around anywhere in the building, and it showcases cream brick on all of its exterior and interior walls. The interior walls have beautiful brick archways over the doors. The brick is a very clean, white color, much whiter than most cream city brick. It is also  rare to find cream brick this clean since it gets discolored very easily due to its porosity.



This is the whitest cream city brick I have seen.

According to the Watertown Historic Society, the entire building was covered in an incredibly ugly metal and concrete facade. Apparently the brick was in good shape underneath the facade, and in 2003 the building was added to the National Register of Historic Places, along with many other buildings on Main St. Watertown was a large producer of cream bricks, with two brick factories. Many cream brick houses can be found in Watertown, as well as old factories and almost the entire main street. This building is the perfect example of beautiful historic architecture that exists all over southern-eastern Wisconsin that has been covered up, painted, or generally forgot about. It's great to see a renewed interest in this part of our history, and I'm happy that a store I was so connected to as a teenager is taking good care of the building.








Firing Process of Cream City Brick

I am going to preface this article by saying I am not a chemist; although I do have some chemistry background with my engineering degree. If any chemists read this, I would love to hear from you in the comments section, since I am still trying to understand this process.

Being a potter, and someone who is very interested in the chemical processes that take place in of firing clay and glazes, I wanted to know more about the firing process of cream bricks and why they become a cream color when the clay is red or purple. Most of the information I have found comes from two reports done by the University of Wisconsin in 1902 and 1906. In "The Clays of Wisconsin and their Uses", Dr Heinrich Ries of the UW Geology department describes this process.  I will combine his description with the research I have done on glazes to attempt to describe this process. I still would like to learn more about it.

An important process that takes place in the firing of these bricks is the calcination of calcium carbonate. Calcination is a process that takes place when any carbonate is heated to a certain temperature. Carbon dioxide is driven off, leaving the oxide of the element. This process is most common in the manufacturing of quicklime for concrete, which is the conversion of CaCo2 to CaO, which is why it is named calcination. It is a process that is used in the production of some glaze ingredients, because it results in a more stable end product, where the color or final mass is already known. For calcium, this occurs at around 1600 deg F. When this point is reached in the brick making process, the brick becomes very porous and fragile. According to Ries, it is important in this process to reach a higher temperature, then a chemical reaction takes place between the lime, silica, and alumina, resulting in a complex silicate compound. When this happens, Ries states that the lime destroys the red coloring of the iron. I have not been able to find any more information on this chemical reaction, and hope to investigate it further with several chemists that I work with. Wollastonite is a compound used in ceramic glazes. The formation of it sounds very similar to this process; it is a compound of silica and calcium that contains small amounts of magnesium and iron. It forms when dolomite or limestone are heated to around 2300 deg F, and is white in color.  The bricks are only fired to around 2100 deg F. I am wondering if due to the high amount of flux this clay contains, it is similar to the Wollastonite process, but is happening at a lower temperature. If any chemists out there could weigh in on this, I am very curious to learn more. Above 2000 deg F, calcium becomes a flux and begins to melt the clay. This is desirable for a glaze, but not for a brick. Full vitrication not of the brick is also not ideal. Since vitrified bricks conduct heat well,  they make poor insulators for houses in cold climates. 

Ceramic Glaze

I recently finished building an outdoor kitchen out of historic cream bricks from Fort Atkinson. This project involved a lot of brick cutting with a wet saw. It was incredibly dirty and unpleasant work; however one thing that struck me after a day of cutting was the water mixed with the dust from the cut bricks, and made a wet clay. I thought it was really cool that I was basically reconstituting clay that was originally dug up from Wisconsin a century and half ago.

As a potter, it got me to wondering more about the clay and its uses in ceramics. I have since learned that due to the high calcium and magnesium levels, it is unsuitable to use as a ceramic clay body, since both act as fluxes and lower the melting point enough that the clay starts to melt above 2000 deg F. Since then, I have been very interested in developing a glaze out of recycled cream bricks.

Thanks to research that has been done on this clay and the brick making process over 100 years ago, I have a very good idea of the exact chemical composition of these bricks. With my research into glaze chemistry, I was able to formulate some excellent glaze recipes with the addition of a few ingredients. To make this glaze, I ground a brick into dust using a belt sander. My goal was to maintain cream city brick as the main ingredient, and only add enough to make it a viable glaze. I recently got my first test pieces back from a cone 6 firing and was extremely happy with most of the results. I have run the successful samples through the boiling water to frozen water test multiple times, and they exhibited no crazing. These glazes contain 60% cream city brick dust by mass.
 

I am very excited to continue testing on these glazes, I would love to make pottery with a glaze made from brick scraps from my parent's historic barn, and it would be a great way to carry on the legacy of the many cream brick buildings that are being taken down each year. I am in the process of constructing a ball mill to ramp up my production of these glazes, and hope to post many more examples soon.

Cream City Bricks

Wisconsin has many unique things to be proud about. Many of these are obvious to most people, like our dairy industry, the Green Bay Packers, and being a national leader in many other areas of food and beverage production. This site is dedicated to another unique feature of Wisconsin, one that is probably not on many people's radar, but that has greatly shaped the architecture and development of much of Wisconsin. It is Cream City Brick, the cream colored brick unique to southeastern Wisconsin that built our towns and cities, and jump started our industrial development in the 1800s.

Cream City Brick Fachwerk barn on my parents' farm.

Growing up in rural southern Wisconsin, I was surrounded by this cream colored brick, although I did not pay much attention to it until very recently. The entire downtown of Watertown, where I grew up, is built out of it, as are most towns in southeastern Wisconsin. After recently completing an amateur masonry project in my back yard, I have developed an interest (obsession) with this brick. This blog will feature photos from all over Wisconsin showcasing the beautiful architecture of our state, most of which was built with this brick.

Cream City Brick is most famous in Milwaukee, since it is the largest city in Wisconsin, and the entire downtown area was built out of it in the mid 1800s. Milwaukee became known as the Cream City, since it's downtown was so bright and light colored compared to the red or brown brick construction of most cities in the US. Cream City Brick is equally prevalent in all small towns as well. In Watertown many people call it Watertown brick, so I think there must have been a local pride for it going way back.

My completed outdoor kitchen project.

What makes Cream City Brick so unique, and why doesn't it exist anywhere else? It has to do with the clay in the glaciated portion of Wisconsin. The predominant bedrock of this region is dolomite and limestone. Dolomite is composed of calcium magnesium carbonate, and limestone is calcium carbonate. When the glaciers came through, they ground this bedrock into a fine clay, and deposited huge beds of clay along river banks and the shores of Lake Michigan. This clay is very unique in its chemical composition compared to most brick-making clays. It is very high in calcium and magnesium. These two elements are crucial to the color of the brick, as well as it's strength and composition. The great abundance of this clay fueled the brick-making industry all over Wisconsin. Most towns had their own brick factories which supplied bricks for their own construction, and were shipped all over the country and beyond. Production remained strong until the turn of the 20th century, when concrete construction replaced the demand for brick. Thankfully, due to their solid construction, most cream brick buildings in Wisconsin still stand, and the often ornate architecture they were constructed in can still be appreciated today.