James Mack Gerstley and Elizabeth Lilienthal married at the home of Madeleine Russell in Atherton in 1934. In the mid-1930s, James Mack Gerstley started working for the Pacific Borax Company in Los Angeles. By 1950, he had become president of the company, which later became known as U.S. Borax and Chemical Co. The company was cemented in the popular imagination by its 20-mule team, which became an icon of the American West. James Mack and Elizabeth had two children, Ann and Jimmy (James). Gerstley was also an active philanthropist in the Bay Area, working particularly on local arts and culture. He was one of the co-founders of the Asian Art Museum in San Francisco and was instrumental in securing for the new museum the Avery Brundage collection. Elizabeth was also an active philanthropist. James and Elizabeth both died in 2007 at the respective ages of 99 and 94.
The collection consists of family papers, scrapbooks, photographs, and photo albums. The family papers include some correspondence, a small amount of material from James Mack Gerstley's tenure at Borax, and historical/ biographical materials about the Gerstley and Mack families. There are a few autograph albums and scrapbooks in the collection as well. The bulk of the collection is made up of photographs and photo albums documenting the history of the Gerstley, Mack, Lilienthal, and Sloss families as well as the travels and milestones of James Mack and Elizabeth Gerstley and their children.