Aerial view of a portion of the US Borax mine. The edge of the one-and-a-half-mile long pit is at the lower left of the photo. photo courtesy of U.S. Borax

The US Borax mine, in the northwestern Mojave Desert, is the largest borate mine in the world, supplying more than half of the worlds borates. The site consists of a refining and packaging complex adjacent to a 1.5 mile long open pit, and several hundred acres of rectangular evaporation ponds.

The substances obtained from the borates extracted from this deposit are used in all sorts of products, from soaps to jet fuels. Boron in particular is an element that has many applications in aerospace and military technologies. It is a component in high-strength fiber composites and in rocket fuels. The Air Force's Phillips rocket propulsion lab at Edwards AFB, located directly across the highway from the mine, is a customer.

The mine and refinery complex employs over 800 people. It was established in the late 1920's, after a large source of borax was discovered here. Prior to this time, borax was mined out of Death Valley and hauled to the railway at Mojave by the famous "20-mule team". Once mined with tunnels, US Borax is now an open pit mine, with a pit one mile long and a half mile wide and 500 feet deep.

US Borax is owned by the British mining company RTZ, which owns Kennecott and has several other well known subsidiaries. RTZ is currently the largest mining company in the world, with 47 mines and processing plants in 35 countries.

There are two other major producers of borates in the world. One is nearby at Trona, adjacent to China Lake Naval Weapons Center, and the other is a mine in Turkey.

CLUI researchers recently visited the US Borax mine as part of the research for the Route 58 Guide. publication. The mine will also be included in the Land Use Database.