Black Diamond, California

The Pittsburg Historical Museum

The Pittsburg Historical Musuem is located in former Pittsburg Post Dispatch building within the industrial town of Pittsburg, California, which was formerly called Black Diamond.

The Post Dispatch had been the primary newspaper for the town of Pittsburg.

The museum has an extensive exhibit on the Italian Americans who lived in the town. During World War II, hundreds of Italians were sent to internment camps in Concord, Dublin and other areas. It was not until the William Jefferson Clinton administration that the U.S. Congress officially recognized that Italians had been interned during World War II.

Black Diamond, California

The Mount Diablo Coal Fields – The Largest Former Coal Mines In California

The Black Diamond Mines East Bay Park entrance near Antioch, California.

In 1849, the Mount Diablo Coal Fields, also known as the Black Diamond Mine, was founded, shortly after Army Lieutenant William Tecumseh Sherman, whom later gained fame as a General during the U.S. Civil War, founded the town of Black Diamond.

Historical marker at the entrance of the Mount Diablo Coalfield, which is also known as the Black Diamond Mine.

The town of Somersville was one of five towns that were established within the Mount Diablo Coal Field, south of the town of Black Diamond.

The Black Diamond Mines had more coal output than any other set of mines within the state of California and continued to operate until 1900. Ultimately, the rising cost of mining coal, and the increase of the demand for oil due to the increase in automobile usage, lead the owner of the Black Diamond Mines to cease operations.

After the coals mines closed, the miners and their families, moved out of the five towns, leaving the various buildings abandoned for two decades.

A sand bunker at the Hazel-Atlas Mine in 1933.
The Greathouse Portal Sand Búnker in 1948.

In the 1920s mining operations for silica-rich sand, by the Hazel-Atlas Glass Company for the production of glass, began at the Black Diamond Mines. Sand mining continued until the 1940s, and the five mining towns became “ghost towns”.

A former residence on the Black Diamond Mine.

Many of the miners who worked at the Black Diamond Mines are buried in the Rose Hill Cemetery.

Presently the former coal mine is under the ownership of the East Bay Park District as the Black Diamond Regional Preserve.

The entrance to the Black Diamond Regional Preserve hosts the Sidney Flat Vistor Center.

After the Black Diamond Coal Mines were abandoned the cemetery was vandalized frequently and grave markers were stolen. However, the grace makes for Walter E. Clare was returned when Black Diamond became a regional park.

The East Bay Regional Park staff give mine tours within one of the former Eureka mine.

The entrance to the mine within the Eureka Slope.

Many of the trails on top of the former mines lead to various hills within the Mount Diablo Foothills.

The author Philip Andrew Hamilton on one of the scenic hills, within the Black Diamond Mine Regional Preserve.