U.S. Borax Operations

Pioneering Progress

We are a global leader in industrial mineral supply and science. We provide approximately 30% of the world’s supply of refined borates—remarkable minerals that are essential to life and to modern living—from our world-class Rio Tinto U.S. Borax mine in Boron, California, about 100 miles east of Los Angeles. As part of the Rio Tinto Group, an international mining and resources company, we serve more than 500 customers in 1,700 locations across 100 countries. Our customers rely on boron and borates to create an extraordinarily diverse range of borate products.

We have more than 30 industrial, agriculture, and specialty products that are sold under the iconic 20 Mule Team® Borax brand, known worldwide for its quality and American Old West heritage. Learn more about our company and the people who are committed to providing boron for modern living.

Rio Tinto Borax mine

U.S. Borax Operations Today

U.S. Borax is acknowledged as the world leader in borate technology, research, and development. Technical support for customers, product quality, and supply reliability are the pillars of our commercial commitment.

As a global leader in industrial mineral supply and science—operates mining, refining, and shipping facilities on four continents, U.S. Borax distinguishes itself through:

  • Cutting-edge research and development
  • World-class safety, environmental, and community practices
  • A commitment to constant innovation and improvement

We maintain a global network of sales offices and stock points. Our researchers work to advance borate science while pioneering new products and applications that harness the many properties of boron.

Sustainable Development

Sustainable Development

Our commitment to protecting the environment dates back to the early days of U.S. Borax. Back in 1916, company officials helped write the language that was adopted by U.S. Congress to establish the National Park Service. Today, we continue that commitment to ensuring that our practices and products are socially, environmentally, and economically sustainable.

  • Land and water
  • Wildlife
  • Energy and waste reduction

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The heart of U.S. Borax is the open-pit mine in Boron, California, one of two world-class borate deposits on the planet. What began as an underground mine in 1872 is now California’s largest open pit mine and one of the richest borate deposits on the planet. In California, U.S. Borax operates its principal mine and refinery in Boron, a refinery and shipping terminal in the Port of Los Angeles, and a trona mine in Owens Lake. Learn more about our operations in California.

Our worldwide organization also includes a distribution and packaging facility in Rotterdam, the Netherlands; a refinery and distribution facility in Coudekerque, France; a packaging and distribution facility in Nules, Spain; and sales and customer service centers around the world. For information on Rio Tinto’s Jadar development in Serbia, please visit Jadar’s web site


Rio Tinto Borates Careers

Careers with U.S. Borax

Looking for a career that matters, with a company that cares?

Join U.S. Borax and help us achieve our mission: supplying the world with refined borates, remarkable minerals that are essential to human progress and modern living.

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Commitment to Our Communities

We prioritize commitment to our communities—both those that we operate in and those that we serve. In Boron, California—our home since 1872—we maintain the historic Borax Visitor Center, which has welcomed more than 125,000 visitors. Our company also teams with area leaders to support local nonprofit organizations through the Borax Visitor Center Foundation. And we encourage all our employees to take an active role as volunteers within their home communities.


U.S. Borax traces its roots to California’s Death Valley, where borate deposits were discovered in 1872. The 20-mule teams that U.S. Borax used to haul ore out of the remote desert live on as a symbol of the company’s commitment to innovation. The current open pit in the Mojave Desert began as an underground mine in 1927, and Boron Operations was converted to a surface mine in the late 1950s; extensive facilities for refining the ore were also built at that time. In 1980, U.S. Borax built its boric acid plant, securing the company’s position as the world’s leading boric acid supplier.

The mule teams that hauled borates out of our original mines in Death Valley are long gone, but the symbol endures in the 20 Mule Team Borax product brand. In the marketplace, this brand is the mark of superior product quality and consistency, supply reliability, technical support, and service. Today, U.S. Borax is acknowledged as the world leader in borate technology, research, and development.

2012: Asia
Scheduled opening of Asia Technology Center
2009: China
Changshu, China distribution center opened
2007: Denver, CO
Global headquarters moved to Denver, Colorado
2004: Serbia
Discovery of lithium-borate deposit in Serbia
2003: Argentina
Borax Argentina's boric acid plant began production
2003: Achievement
Global operations achieved ISO 9001 certification for excellence in Quality Management
2002: Achievement
Chrysler Natrium, world's first sodium borohydride-powered, zero emission vehicle made pit stop at U.S. Borax's Boron Operations
2001: Achievement
Company formed partnership with Millennium Cell to develop safe, clean fuel alternative based on sodium borohydride
2000: Achievement
Global operations achieved ISO 14000 certification for excellence in environmental management
1999: Pasadena, CA
Twenty Mule Team's last ride in Pasadena Rose Parade, world's largest parade
1998: China
New sales offices established in China
1997: Boron, CA
Company celebrated 125th anniversary; Borax Visitor Center opened in Boron, California
1996: Achievement
Global operations achieved ISO 9002 certification for excellence in Quality Management
1994: Guildford, England
European headquarters moved to Guildford, England
1993: Valencia, CA
Global headquarters moved to Valencia, California
1992: Italy
Borax Italia established; Borax Espana relocated to Nules
1988: Achievement
Boraxo/Borateem/20-Mule Team product lines sold to Dial Corporation
1967: Acquisition
Borax acquired by Rio Tinto, one of the world's leading mining companies
1963: Netherlands
Borax NV (Rotterdam) built; Deutsche Borax formed
1925: Discovery
Boron deposit discovered
1923: Wilmington, CA
Wilmington refinery built
1922: Spain
Borax España refinery constructed in Barcelona
1905: Benelux
Borax Benelux acquired
1902: France
Borax Français established
1883: 20 Mule Team
Twenty mule teams established to haul borates
1881: Discovery
Borates discovered in Death Valley
1872: Discovery
Company founder F.M. "Borax" Smith discovered borates in Nevada
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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 east of Los Angeles.  Learn more about Rio Tinto

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