Stockton Fire and Enamel Brick Company
Letterhead donated by Chris and Sandra Ingram
In 1907, the Stockton Fire and Enamel Brick Company was organized with Myers J. Gardner as president,
Charles M. Jackson as vice-president, Thomas A. Nelson as secretary and treasurer, and George S. Wheatley as
manager. The plant was built on the west side of the Southern Pacific railroad near California and 9th
streets in south Stockton. Brick production began in October of 1907. From 1909 to 1916, the sales of face and enamel
bricks were handled by the Golden Gate Brick Company based in Antioch. In 1912, the Stockton company opened
an office at 322 Montgomery Street in San Francisco, with Eugene Corrigan as the sales representative.
The company obtained clay from Tesla in Alameda County, Ione in Amador County, Valley
Springs in Calaveras County, and Lincoln in Placer County. The raw materials were
delivered to the Stockton plant by rail.
Early view of the plant of the Stockton Fire and Enamel Brick Company in the southern part of Stockton.
At the plant, the clay was dumped from the cars and then shoveled into a dry pan, where the clay was
ground to a fine powder. The powder dropped through a screen into a cup elevator, which conveyed the clay
to the top of the building. The clay was dropped through a screen into a number of bins about 20 feet
below. From the bins, the ground clay was transported by pipe to the pug mill, where it was mixed with
water and sand to proper consistency. A 25 h.p. induction motor powered the pug mill. The mixture passed
down a chute into an American brick machine on the ground floor. The brick machine was run by a 75 h.p.
induction motor. The compressed clay was conveyed from the brick machine by a belt to an automatic cutting
table, where the clay bar was cut by wires into bricks. Face bricks were taken to the drying room using
waste heat from the kilns. Enamel bricks were conveyed to the glazing department, where they were dipped in
the glazing solution and either taken to the drying room or allowed to dry in the sun. After dried, the
enamel bricks were again dipped in the glazing solution, right before they were put in the kiln to be burned.
There were two brick pressing machines for making face brick and firebrick. They also made hand-molded
material and linings.
There were six round, 36-foot, down-draft kilns, fueled by oil, and each kiln had a capacity of 60,000 bricks.
Five of the kilns were connected to an 80-foot tall square chimney. One was connected to a 40-foot tall round
chimney. There was also a 10-foot diameter kiln connected to a 26-foot tall square chimney. The clay products
were fired to a temperature of 2,000 degrees F. The products were fired for seven days
and then allowed to cool for seven days. The products were removed from the kilns and transported to market
by the Southern Pacific Railroad Company.
This company made smooth face brick in different colors: white, yellow, tan, salmon, rose, red, and brown. The
enamel bricks were mat glazed of all colors or a mottled texture. These face bricks were of standard size, 8 1/4 x
4 x 2 1/4, with rounded rectangular frog and recessed block letters of the brand name "STOCKTON." Later, the face
brick was made the same size as the 9-inch long firebrick and without the frog. The unusually large size of the
face brick is one of the distinctive characteristics of their brick. The pressed brick was also 9 inches
long. A red paving brick with the brand name "SIERRA" was also made. The firebrick was a standard 9-inch brick
in white, gray, yellow colors with quartz grog. These bricks were stamped on the face with the brand names of
"STOCKTON," "GASCO," "GASCO XX," "DIABLO," "CARNEGIE," "YOSEMITE," and others. The most distinguishing features
of these bricks are the light colored clay body, usually white or yellow, and the wire-cut faces. Some firebricks
were dry pressed and this process became more important after the company changed its name to the Stockton Fire
Brick Company in 1920. The STOCKTON brand firebrick probably was the first firebrick made. The CARNEGIE brand
probably was added around 1912, after the closing of the Carnegie Brick Works at Carnegie. In 1916, the company
experimented with magnesite and silica bricks. Magnesite brick production began in 1918, with magnesite obtained
from California mines. A large contract for 1 million firebricks for the generator houses of Pacific Gas and
Electric Company in 1917 may have been the start of the "GASCO" brand of firebricks.
Some of the buildings where face or enamel bricks were used include the Y.M.C.A. building, Mayfair Apartments,
and the Southern Pacific Depot in Stockton, the West Side Bank in Tracy, and the light wells in the Magnin
building, Eagle Apartments, U.S. Post Office, and the Lincoln Realty building in San Francisco. The Stockton
fire bricks were used in the Hercules Powder Works at Hercules, the Penn Copper Mines in Calaveras County,
oil pumping plants of the Shell Oil Company, the garbage disposal plant at the Panama-Pacific Exposition, the
generator plants of Pacific Gas and Electric Company, the Moore and Scott shipbuilding plant in Oakland, the
Pacific Coast Shipbuilding Company, and the Merchant Fleet Corporation.
Initially, the plant employed 25 workers, who were capable of producing 50,000 bricks per day. James W. Hislop was
the first superintendent, who was formerly the foreman at the Carnegie brick plant. In 1912, F.O. Wanka, who
was also from Carnegie, was hired as superintendent. In 1914, John T. Roberts became the manager. By 1917, the
plant was producing 500,000 bricks per month, most of which were firebrick, and employed 78 workers. By 1920, the
declining market for face brick forced the company to reorganize and concentrate only on making firebricks,
which were in high demand. The company changed its name to the Stockton Fire Brick Company (see the
Stockton Fire Brick Company).
Stockton Fire and Enamel Brick
Firebrick is white, gray, or yellow, with light orange flashing common on the sides. The surfaces are smooth
and usually crackled. Visible clasts are subangular white quartz and irregular to round brown iron spots, often
with blister holes, up to 3/8 inch across and each constituting up to five percent of the clay body. Internally,
the clay body is granular and spalls easily. The edges and corners are often chipped or broken. Some sides
may be undulating with stack indentations. The faces contain curved wire-cut marks and pits and are usually
rougher than the sides. One of the faces may display many longitudinal, parallel lines of dashes, which may be
the conveyor belt imprint. The marked face is usually centered with the brand name recessed in block letters.
The "STOCKTON" brand name spans 5 1/8 inches in length and is 3/4 inch in height. The name may be difficult to read
on some. The "YOSEMITE" brand name spans 5 inches and is 3/4 inch in height. The "CARNEGIE" pressed oversized block
has the name recessed in thin block letters that spans 4 7/8 inches in length and 3/4 in height. The logo is an
"S" 3/4 inch in height inside a circle that is 1 1/8 in diameter. Another type of logo is a double-lined circle
3 inches in diameter with an outline of an "S" inside measuring 1 3/4 inches in height and 1 5/8 inches wide. The
"GASCO" brand name spans 4 1/2 inches and 3/4 inch high. The "GASCO XX" came in two sizes. In the smaller double X
version, the brand name "GASCO" spans 4 1/4 inches and 3/4 inch high, and the underlying "XX" spans 1 3/4 inches
and 5/8 inch high. In the larger double X version, the brand name "GASCO" spans a tighter 3 1/8 inches and 5/8 inch
high, and the larger underlying "XX" spans 2 inches and 1 inch high. The "DIABLO" example is a dry pressed brick,
partly destroyed on the face, but shows the brand name "DIABLO" that spans 5 5/8 inches and 3/4 inch high, with
only the letters "D" and "B" in view. These firebricks were made using either the stiff-mud process by an extruded,
wire-cut brick machine or soft-mud process using a brick press. Length 8 5/8 - 9 1/8, width 4 1/4 - 4 3/8,
height 2 3/8 - 2 1/2 inches.
View of the marked face of a Stockton firebrick. Note the curved wire-cut marks and white quartz grog on the face.
View of the side of a Stockton firebrick. Note the typical yellow tint of this brick.
View of the marked face of a Stockton firebrick. This one displays a faint name plate outline with 1/4-inch wide holes at the ends.
View of the side of a STOCKTON firebrick showing the typical orange flash pattern.
View of the marked face of a Stockton firebrick displaying the "S" logo. Donated by Mike Peters
View of the marked face of a YOSEMITE firebrick. Donated by Petter L. Rosenquist.
View of the marked face of a GASCO firebrick.
View of the marked face of a GASCO XX firebrick. The double X is 5/8 inch high.
View of the marked face of a GASCO XX firebrick. The double X is 1 inch high.
View of the marked face of a GASCO XX firebrick. This has a red clay body with white quartz grog.
View of the marked face of a DIABLO firebrick. Only the "D" is visible. The rest of the name has been destroyed or covered by mortar. Donated by Petter L. Rosenquist.
View of the marked face of a CARNEGIE pressed oversized block displaying the "S" logo.
Enamel brick is white, green, tan, or other colors. Some display speckled patterns. The glaze was applied to
one, two, or three sides. Enamel was also applied to ornamental shapes. The enamel surface is
not always perfectly smooth, but has a bumpy feel to it. The enamel was available in gloss and mat. The surface
on some are crackled. The brick was made by an extruded, wire-cut machine.
Length 8 - 8 1/4, width 3 7/8 - 4, height 2 1/4 - 2 1/2 inches.
View of the side of the Stockton "enamel white mat no. 21."
View of the side of a Stockton enamel tan mat.
View of the side of a Stockton enamel green gloss finish.
View of the side of a Stockton enamel speckled mat.
Wire-Cut Face Brick
Wire-cut face brick is white, yellow, gray, buff, salmon, red, or purple. The colors are often mottled or streaked
with lighter colors. Internally, the clay body is fine and compact with visible grains of white
subrounded quartz and brown iron spots up to 3/8 inch across and both constituting up to 10 percent
of the clay body. These minerals are visible on the surface. The edges and corners are sharp. The
sides are smooth and often crackled. Some sides feel lumpy and display transverse grooves or streaks.
The faces have curved wire-cut marks and minor pits. One face may show longitudinal parallel lines of dashes,
which may be the imprint of a conveyor belt. The marked face has two styles. An earlier style contains a
rounded rectangular frog that has beveled sides and measures 6 1/8 inches long, 2 1/8 inches wide, and
1/16 inch deep. Centered in the frog is the brand name "STOCKTON" recessed in block letters, which span
5 3/8 inches in length and 3/4 inch in height. The rug brick typically has 21 deep transverse grooves on
the side and 9 or 10 deep transverse grooves on the ends of the brick. The grooves are evenly spaced. The
face brick was made using the stiff-mud process by an extruded, wire-cut machine.
Length 8 1/4, width 4, height 2 3/8 - 2 1/2 inches.
View of the marked face of a white Stockton face brick showing the rounded rectangular frog.
View of the unmarked face of a Stockton face brick showing the dashed line imprint of a conveyor belt (lower left).
View of the side of a Stockton tan face brick.
View of the side of a Stockton tan face brick with visible clasts.
View of the side of a Stockton buff face brick no. 18."
View of the side of a Stockton red buff face brick showing the transverse streaks.
View of the side of a Stockton purple face brick.
View of the side of a Stockton yellow speckled face brick.
View of the side of a Stockton salmon speckled face brick.
View of the side of a Stockton gray speckled face brick.
View of the side of a Stockton smooth orange red face brick.
View of the side of a Stockton red face brick showing transverse streaks and clasts.
View of the side of a Stockton smooth red face brick.
View of the sides of the Stockton buff rug bricks in two shades of color.
Pressed Face Brick
Pressed face brick are the same colors as wire-cut face bricks. All surfaces are smooth and look the same.
The surface may show crackles and small pits and visible white quartz and brown iron spots up to 3/8 inch
across. Some sides may show stack indentations. The faces often display longitudinal stack indentations or
grooves. The edges and corners are sharp. The internal clay body is granular and spalls easily. The marked
face is centered with the brand name "STOCKTON" recessed in block letters. A faint outline of a name plate
may be visible, but often not. At the ends of the plate are two round dimples 1/4 inch in diameter. On the
smaller sized brick, the name spans 5 1/4 inches and is 3/4 inch in height. On the larger brick, the name
spans 6 inches and is 3/4 inch in height. Pressed brick are larger than the wire-cut brick and coarser grained.
They are made by the soft-mud process using a brick press machine.
Length 8 7/8 - 9, width 4 3/8 - 4 1/2, height 2 1/2 inches.
View of the marked face of a Stockton buff pressed brick.
View of the side of a Stockton buff pressed brick.
View of the side of a Stockton mottled red pressed brick.
The paving brick is a dark red pressed brick. It has perfect form with straight rounded edges and rounded corners. The surface has
a sippled texture owing to the coarse grains in the clay. The marked face displays the brand name "SIERRA" recessed
in block letters inside a 1 1/2 inch wide rectangular name plate. On each side of the name are long rectangular raised lugs
set perpendicular to the length of the brick. These lugs measure 2 1/2 inches in length and 1/2 inch wide. Between the name and
lugs are 1/4 inch diameter screw imprints. Around the edges of the marked face is a prominent ridge which marks the boundary
of the face plate in the press. The interior is composed of a coarse granular vitrified clay body with less than 2 percent tiny
specks of black iron oxides. Length 8, width 3 5/8, height ?.
View of the marked face of a SIERRA paver. Photo courtesy of Steve Curtiss.
View of the marked face of a SIERRA paver. Photo courtesy of Douglas S. McIntoch.
Architect and Engineer, September 1909, p. 116.
Copyright © 2009 Dan Mosier
Architect and Engineer, January 1910, p. 108.
Bradley, W.W., Brown, G.C., Lowell, F.L., and McLauglin, R.P., Mines and Mineral Resources of Portions
of California, Part 4: The Counties of Fresno, Kern, King, Madera, Mariposa, Merced, San Joaquin,
Stanislaus, California State Mining Bureau 14th Report of the State Mineralogist, for the Biennial
Period 1913-1914, 1916, p. 429-634.
Brick and Clay Record, July 30, 1907, p. 37.
Brick and Clay Record, v. 39, no 2, 1911, p. 56.
Brick and Clay Record, v. 40, no 3, 1911, p. 150.
Brick and Clay Record, v. 41, no 9, 1912, p. 364.
Brick and Clay Record, v. 46, no 2, 1915, p. 180.
Brick and Clay Record, v. 46, no 9, 1915, p. 878.
Brick and Clay Record, v. 48, no 3, 1916, p. 258.
Brick and Clay Record, v. 49, no 3, 1916, p. 242.
Brick and Clay Record, v. 52, no 1, 1917, p. 56.
Brick and Clay Record, v. 52, no 5, 1917, p. 428.
Brick and Clay Record, v. 52, no 7, 1917, p. 607.
Brick and Clay Record, v. 53, no 4, 1918, p. 313.
Brick and Clay Record, v. 64, no 7, 1924, p. 518.
Brick and Clay Record, v. 77, no 8, 1930, p. 412.
Dietrich, Waldemar F., The Clay Resources and the Ceramic Industry of
California, California State Mining Bureau Bulletin 99, 1928, p. 209-212.
Laizure, C.M., San Joaquin County, California State Mining Bureau 21st Report of the State
Mineralogist, 1925, p. 188-189.
Peters, Mike, written communications, 2015.
Ramos, Karen, Cesar Chavez Library, Stockton, provided reference materials on Stockton bricks
and brick buildings, 2006.
San Francisco City Directories, 1915-1920.
Sanborn Map Company, Stockton Fire and Enamel Brick Company, Stockton, 1917.
Stockton City Directories, 1907-1920.