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 northeast of Los Angeles. As part of Rio Tinto , 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.

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.


Boron and Wilmington Operations overview tour

Take a tour of the largest open pit mine in California as well as our shipping facility in the Port of Los Angeles. You'll meet the people who make our operation a success as well as the technology we use to bring you essential materials for modern life.

Watch the video  ›

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

Learn more about our sustainable development  ›


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. Rio Tinto also has a lithium project site in Jadar, Serbia.


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.

Explore jobs with us  ›

Mules at the parade

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.

More About U.S. Borax Operations

Lithium: A Sustainable Source in the Desert
A breakthrough method for extracting lithium from waste rock at our Boron, California mine presents exciting opportunities for producing battery-grade lithium... Read More
U.S. Borax: Empowering Women in Engineering
As we celebrate International Women in Engineering Day (INWED), U.S. Borax shines a light on some of the brilliant engineering leaders in our own organization. Read More
The Distinguished “Mule” Status at Boron
Today, the 20 Mule Team is a powerful symbol and represents courage, hard work, and perseverance. Read More

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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