California brick

Laclede-Christy Clay Products Company, Warm Springs plant
Harbison-Walker Refractories Company, Warm Springs plant


In 1948, Laclede-Christy Clay Products Company of St. Louis, Missouri, built a refractory brick plant next to the Western Pacific railroad at 48311 Warms Springs Blvd. near Starlite Way, in Warm Spring (Fremont), Alameda County, California. Laclede-Christy was a well-established refractories company, which started in 1844 as one of the earliest manufacturers of firebrick in the United States, with their first plant in St. Louis Missouri. This company is also known for pioneering the first dry-pressed firebrick dating back to the 1860s. The plant began operations in Warm Springs on December 1, 1948. The company office was located at 391 Sutter St. in San Francisco. The officers were J. A. Kayser, manager, and W. J. Eames, plant superintendent.

Laclede map

Topographic map showing the brickyard property marked "kilns" when it was owned by Harbison Walker in 1961.

The Warm Springs plant consisted of an office, warehouse, and one down-draft kiln, 15 by 26 feet in size. This plant manufactured refractory tank blocks used for lining glass-making furnaces. These blocks were designed for use in all locations in contact with molten glass, and were sold under the trade name "FLUXITE". Unfortunately, I was not able to find an example of this product to include here. This plant also made refractory firebrick which were branded LACLEDE/CAL. Other brick bats found at the plant site included LACLEDE/SPALLAC and other unidentified brands, which were probably shipped from Missouri.

The company used carefully selected Missouri bond clays, which were weathered, blended, and treated, to obtain a mix having the desired purity, plasticity, and strength. The clay was transported to the yard by Western Pacific railcars and dumped in the storage area on the south end of the property. The mix was alternately pugged and aged to secure uniformity, and the blocks were manufactured by a de-airing process. The blocks were carefully dried and their moisture content constantly checked before burning. Specially developed machines were used for kiln loading. The blocks were burned in a gas-fired down-draft kiln. A map shows that there were four round kilns on the east side of the plant building. A very high peak-temperature was maintained over a considerable period of time to insure soaking heat and uniformity of burn. The changes in temperature were carefully controlled at all points in the burning cycle. The complete burning cycle required about 30 days and production capacity ran about 2,000 pounds of fired-product. After burning, the blocks were machine ground to size, 12 by 24 by 36 inches, for speed and accuracy in laying with resultant low cost of installation. From the sample of firebrick found on site, the dry pressed method was used to make standard firebrick at this plant. Products were shipped out on the Western Pacific railroad, which had a spur siding called Curtner, named after a local pioneer rancher.

In 1951, Harbison-Walker Refractories Company of Pittsburgh, Pennsylvania, was interested in purchasing the Warm Springs plant from Laclede-Christy. Harbison-Walker was another well-established refractories company, which started in 1865 as the Star Fire Brick Works at Pittsburgh, Pennsylvania. In 1925, Harbison-Walker established an office in the Hobart Building in San Francisco to introduce its refractories in the western market. The company found that it was more economical to ship raw material to manufacture bricks in California than to ship the fragile bricks directly from its eastern plants. By 1953, Harbison-Walker had purchased the Warm Springs plant. Little is known about Harbison-Walker's operation at Warm Springs, but their 1961 book mentioned that many of the brands of their basic refractory bricks were made there. The basic bricks, probably CHROMEX B, a magnesite and chrome brick, and a silica brick, VEGA, were power-pressed and fired in tunnel kilns at high temperatures. These bricks were sold to steelmaking plants for use in their open hearth furnaces. In 1960, Lincoln A. McGill was the district sales manager in the San Francisco office. The plant manager was Ed Magusiak and they employed about 12 workers.

Because the Warm Springs plant did not make bricks that met the requirements for the steel industry's newer steelmaking processes, they saw a decline in the sales of their products. The plant closed in the summer of 1966. The San Francisco office closed in 1969. The 21-acre property was finally sold in October 1970 to the Hussmann Refrigerator Company for $250,000. The brick plant was razed and a new warehouse was built over the site. The site today is part of the Warm Spring business technology park.

Laclede Brick

LACLEDE firebrick was manufactured from 1948 to 1953 at the Warm Springs plant by Laclede-Christy Clay Products Company. It is buff and uniform in color. It contains a grog of subangular milk white quartz up to 1/8 inch across and about 40 percent by volume. Brown or rusty round iron spots, up to 1/4 inch across, forms about 10 percent of the volume. Some of the larger iron spots are centered with a blister hole. The brick has a smooth surface and a granular texture. The edges are straight but the edges and corners are chipped or rounded from wear. The brick spalls easily. On one of the faces is imprinted the company name on two lines as recessed block letters. The top line is LACLEDE, which spans a length of 5 inches and is 11/16 inch high. The second line is CAL, which spans a length of 1 7/8 inches and is 11/16 inch high. Dry pressed process was used in making the brick. Length 9, width 4 3/8, height 2 1/2 inches.

Laclede firebrick
View of the face of the Laclede firebrick.

VEGA superduty silica brick was made by the Harbison-Walker Refractories Company at the Warm Springs plant from 1951 to 1966. It is composed of finely crystalline high temperature quartz and lime for a strong ceramic bond. The sum of alumina, alkalies, and titania does not exceed 0.35 percent in volume. It was best used in temperatures greater than 1,200 degrees F, and has relatively high melting temperatures of about 3,080 to 3,110 degrees F. It was used in the superstructure of glass-tank furnaces, in the roofs of copper reverberatory furnaces, nickel and copper anode furnaces, and copper wirebar furnaces. The color is gray and uniform. Rounded white quartz grains are less than 1/4 inch across in a very compact fine quartz body. Centered on one of the faces is recessed the brand name VEGA spanning 4 inches and 7/8 inch in height. The letters are in a rounded block letter font style. The faint rounded rectangular outline of the name plate is visible and is 1 inch in height. Length 9, width 5 7/8, height 2 3/4 inches.

Laclede VEGA silica brick
View of the face of the Vega silica brick. Donated by Sandra Kelly.

CHROMEX B is a chrome-magnesite basic brick made by the Harbison-Walker Refractories Company at the Warm Springs plant from 1951 to 1966. It is composed of mostly chromite, with lesser olivine and periclase, which can withstand extremely high temperatures. It was used in the walls and roofs of open hearth furnaces, linings of basic electric steelmelting furnaces, in soaking pits, the bottoms of forge furnaces, linings of copper and nickel converters, sidewalls of copper refining furnaces, bottoms of copper electric furnaces, in aluminum holding furnaces, brassmelting furnaces, and in parts of glass furnaces. The brick is black and uniform in color. The high amount of chrome makes this a heavy brick. On one of the faces is recessed the name CHROMEX on the first line and on the second line "B-65." The shape is a key wedge with length 8, width 4 1/2 - 8 1/2, height 4 1/2 inches.

Laclede Chromex B-65 chrome-magnesite brick
View of the face of the CHROMEX B-65 chrome-magnesite brick.


Argus, Fire Brick Firm Closes, April 4, 1966.

Argus, Refrigerator Firm Buys Fremont Site, October 27, 1970.

American Ceramics Society Bulletin, v. 30, no. 12, 1951, p. 23.

Brick and Clay Record, v. 66, no. 13, 1925, p. 996.

Davis, F.F., Mines and Mineral Resources of Alameda County, California, California State Mining Bureau, v. 46, no. 2, 1950, p. 294.

Harbison-Walker Refractories Company, Modern Refractory Practice, The William Feather Company, Cleveland, 1961.

Laclede-Christy Clay Products Company, Fireclay Refractories, St. Louis, MO, 1947.

San Francisco City Directories, 1925-1969.

U. S. Geological Survey, Milpitas Quadrangle, California, 7.5 Minute Series, 1961.

Copyright 2007 Dan Mosier

Contact Dan Mosier at