Saline Valley
Conn Trudo Borax Works
Borax was discovered in Saline Valley in 1874. Conn and Trudo began a small borax-reduction operation soon afterward, reportedly in 1875, at the salt marsh near the valley floor. Their work preceded both the Eagle Borax Works, which began in 1882, and the Harmony Borax Works, which began operating in late 1883 or early 1884.
The company worked deposits of tincal, a naturally occurring borate mineral. Workers collected the mineral crust from the marsh, dissolved it in boiling water, and allowed impurities to settle before the borax crystallized again. Refined borax was then hauled by wagon out through Waucoba Canyon toward Big Pine and the Owens Valley.
The California State Mining Bureau described the operation in 1896:
"Conn A. Trudo Borax Works lie in Saline Valley, 18 miles north of Keeler. The firm controls about 700 acres, part of which is covered with a crust of crystallized tincal from 6 inches to 2 feet thick, which contains 90 percent borax. The crude material is dissolved in boiling water and drawn off in tanks, where the impurities settle and the borax crystallizes out. Conn & Trudo, of Big Pine, owners."
Report of the State Mineralogist, California State Mining Bureau, 1896
The scale of the work was modest but productive. A National Park Service history notes that Conn and Trudo produced 400 tons of concentrated borax in one year, nearly matching the previous year's output. Borax production continued until 1907. NPS history
Eagle - Harmony Borax Works - Keeler - Big Pine