U.S. Borax History

History of the U.S. Borax 20 Mule Team

​U.S. Borax traces its roots to California’s Death Valley, where borate deposits were discovered in 1872. The first 20 mule team hauled borax a sweeping 165 miles through Death Valley in 1883. Fully loaded with two ore wagons and a 1,200-gallon water wagon, the rig weighed 36.5 tons. Though the expansion of railways led to the 20 mule team’s retirement, the team has lived on for more than a century as a trademark for U.S. Borax.

A recreation of the original mule teams has rode for:

  • 1904 St. Louis World’s Fair
  • President Woodrow Wilson’s 1917 inauguration
  • The dedication of the San Francisco Bay Bridge in 1937
  • 1999 Rose Parade
Today, U.S. Borax is acknowledged as the world leader in borate technology, research, and development.
Death Valley National Park

Death Valley National Park

Stephen T. Mather created the 20 Mule Team® brand when he launched his career at the Pacific Coast Borax Company, which became U.S. Borax before being acquired by Rio Tinto in 1967. It was the start of a lucrative business venture, and one that would lead him from mining to his ultimate calling—helping to create the National Park Service.

Learn more  ›

Rio Tinto Borates Careers

Death Valley Conservancy

The Death Valley Conservancy (DVC) is a non-profit organization that strives to provide support and funding for projects that preserve, protect, or enhance Death Valley Park by improving the Death Valley area’s natural, cultural, and historic resources and the visitor experience. The DVC has full responsibility for managing the restoration of sites such as Ryan Mining Camp, operated by Pacific Coast Borax from 1915-1927.

Learn about the Death Valley Conservancy  ›

Ronald Reagan on Death Valley Days

20 Mule Team Borax on TV

The 20 Mule Team Borax brand originally became a household name through the sponsorship of the radio program Death Valley Days. The program evolved into a TV show in 1952 (now available on DVD). 

Hosting the series in the mid-1960s was the last job Ronald Reagan had as an actor before becoming governor of California.

Learn More About U.S. BorAx History

150 Years in the Mine: Life in Boron
During the early days of borate mining miners battled difficult conditions. Their grit and hard work established a solid foundation, enabling U.S. Borax to gr... Read More
Classic Tales from the Wild West
Realistic writing, renowned actors, and adventurous Wild West narratives made Death Valley Days one of the longest running radio and television progr... Read More
U.S. Borax Operations: Then and Now
This year marks an important milestone in U.S. Borax history as we celebrate 150 years of boron mining operations. Let’s look at the transformation of b... Read More


Company founder F.M. "Borax" Smith discovered borates in Nevada
Borates discovered in Death Valley
The 20 Mule Team appeared at the St. Louis World's Fair
Helped write the language adopted by the U.S. Congress to establish the National Park Service
20 Mule Team rode in the Rose Parade, carrying the parade’s president, and representing U.S. Borax as a national symbol of perseverance
Borax España refinery constructed in Barcelona
Wilmington, California refinery built
Boron deposit discovered at current location
Underground mine opened at current mine location in Boron, California
Donated land to the U.S. government to create Death Valley National Monument
Boron Operations converted to a surface mine, extensive refining facilities built
Borax acquired by Rio Tinto
Boric acid plant built at Boron Operations in California
Boraxo, Borateem, and 20 Mule Team product lines sold to Dial Corporation
Solubor®, an agriculture micronutrient, invented
Donated land and lobbied the U.S. government to create Death Valley National Park
Firebrake® 500, anhydrous zinc borate, developed
Global operations achieved ISO 9002 certification for excellence in Quality Management
Company celebrated 125th anniversary by opening the Borax Visitor Center
Polybor® Flow liquid borate invented;
New sales offices established in China
Twenty Mule Team's last ride with original wagons in Pasadena Rose Parade
Global operations achieved ISO 14000 certification for excellence in environmental management
Company formed partnership with Millennium Cell to develop safe, clean fuel alternative based on sodium borohydride
Chrysler Natrium, world's first sodium borohydride-powered, zero emission vehicle made pit stop at U.S. Borax's Boron Operations
Global operations achieved ISO 9001 certification for excellence in Quality Management
Lithium-borate deposit discovered in Serbia
Granubor® 2 developed for agriculture
Changshu, China distribution center opened
Donated more land to expand Death Valley National Park
The safety award-winning Modified Direct Dissolving of Kernite (MDDK) process facility opened at Boron operations, maximizing the utilization of the ore body in order to meet marketing demands, increasing mine yield by approximately 6-8%
The 20 Mule Team rode in the Rose Parade with brand new replica wagons, 100 years after their first appearance, remaining an icon of history and perseverance in California, and across the U.S.
Watch the video
Two new fertilizer products—Anhybor® and Zincubor®—launched.
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20 Mule Team Borax laundry detergent

20 Mule Team Laundry Detergent Booster

Since 1891, all-natural borax has been an essential ingredient in a multitude of household products, including laundry and multi-purpose cleaning solutions. In 1988, the Dial Corporation acquired U.S. Borax’s consumer products division, including the 20 Mule Team brand laundry detergent. Subsequently, Henkel acquired Dial in 2003.

Learn the many uses of 20 Mule Team Laundry Detergent  ›

U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 500 customers with more than 1,700 delivery locations globally. We supply 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles.  Learn more about Rio Tinto.

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