Pilot Processing Plants

Rio Tinto, Borax Mine, Boron, California

Posted July 23, 2020

Oct. 23, 2019 the Sydney Morning Herald reported “A ‘eureka moment’: Rio Tinto strikes lithium while looking for gold.” Rio Tinto has indicated that it will launch a pilot program at its borax mine in Boron, California, to produce lithium. Workers discovered high grades of lithium as they were searching piles of waste rock looking for gold and other minerals. The lithium is in a concentration higher than rival projects in the United States.

Rio Tinto was investing $10 million for a pilot plant in hopes of becoming the largest lithium miner in the United States. If successful, Rio Tinto would consider investing $50 million to build an industrial-scale lithium processing plant.

The borax deposit in Boron was discovered in 1913 and the claim was purchased by Pacific Coast Borax. Mining began in 1927 as an underground operation. Pacific Coast Borax merged with United States Potash Corporation in 1956 to become U.S. Borax and the mine in Boron was converted to an open pit operation in 1957. The Rio Tinto Group acquired U.S. Borax in 1967. Rio Tinto sold its flagship product lines of Boraxo, Borateem and 20 Mule Team to the Dial Corporation in 1988 and continued to operate the borax mine in Boron.

November 2008 Rio Tinto started the sale of its market-leading borate and talc businesses which included U.S. Borax and the mine in Boron. Rio Tinto was countering an unsolicited takeover bid worth $60 billion from rival BHP Billiton Ltd. The borax and talc units were estimated to be worth $1.2 billion and at the time Rio Tinto had plans to sell $15 billion in assets to repay debt.

January 2009, a Chinese company was one of the groups expected to submit final bids for Rio Tinto’s borates and talc units. Rio Tinto had cut 14,000 jobs, cut capital spending by more than half, and needed to pay down close to $40 billion in debt. After bids came in too low for the borate unit Rio Tinto took the borate business off the market May 2009 while the talc unit remained for sale.

September 2009, Rio Tinto opened contract negotiations in preparation for the Nov. 4, 2009, contract expiration. Rio Tinto proposed changes to the agreement that would eliminate seniority, allow for outside contracting and hiring temporary workers, and eliminate important strategic work from the bargaining unit. An agreement was not reached, and Feb. 1, 2010, Rio Tinto locked out 570 union workers from the mine in Boron. Hundreds of replacement workers were brought in. The 15 weeklong lock out ended May 2010 when the union ratified a new six-year contract.

March 2, 2018, Rio Tinto released their 2017 annual report which included significant changes in estimates of ore reserves and mineral resources at the borax open pit mine in Boron, California, compared to the previous estimates in the 2016 annual report. The Boron ore reserves have decreased by 6 Mt, from 22 Mt to 16 Mt. The operating life of the Boron mine has been reduced by seven years and is anticipated to run until 2042.

Apparently undaunted by the new information of lower ore estimates and reduced mine run time, or having other plans in mind, the November 2019 edition of Transform Magazine announced that US Borax – Rio Tinto and the branding company Refactored won a Silver award for the best rebrand of a digital property. Refactored completed a full site redesign of the highlights of the global importance of mineral-based products for Rio Tinto and the 20 Mule Tam Borax brand.

The result was a redesign of Rio Tinto’s U.S. Borax website to promote the company’s core story of a history of excellent and a reputation for pioneering essential elements for modern living. The benefits made it easier for industry experts and the layperson site visitor to find information. New technical content written in easy to understand language was provided. And it communicated the importance of borates to modern living and provide access to documentation, product guidelines and information.

In addition to the rebranding of Rio Tinto’s U.S. Borax website, Rio Tinto’s nonprofit organization worked to build a replica of the historic 20 mule team wagons. The work on the replica 20 mule team wagons began in 2014 and were crafted by a shop in Montana that specializes in handmade horse-drawn vehicle and wheelwright. Two replica wagons and a water tender were completed in 2019.

The 20 mule team wagons only operated for six years between 1883 and 1889. The route was from the Harmony and Amargosa borax works in the Death Valley area to Daggett, California and later to Mojave, California. Rio Tinto sold the 20 mule team product lines to the Dial Corporation in 1988. The Dial Corporation is owned by the Henkel chemical company headquartered in Dusseldorf, Germany. But even with the 20 mule team wagons only operating for a few years and Rio Tinto selling off the product line, the public relations image of that history is particularly important. The 20 mule team brand still appears on Rio Tinto’s U.S. Borax website and business documents and a brief history is hyped on their job notifications.

With the time and cost of rebranding Rio Tinto’s borax website and building a replica set of 20 mule team wagons, it is apparent that if Rio Tinto is no longer mining borax in Boron, California, they must be planning to mine borax elsewhere.

Besides the waste rock which contains lithium at the borax mine in Boron, California, Rio Tinto holds other borax claims in California. And since lithium was found at the Boron borax mine it could possibly be found at their other borax claims.

One such location is the White Monster claim which is a placer claim patented Nov. 5, 1889. The White Monster is the earliest borate claim in the Upper Furnace Creek Wash of the Death Valley area. Information and documents have revealed that Rio Tinto is interested in mining the White Monster claim and in 2009 its value was placed from $6 to $12 billion. The claim is located inside the Death Valley National Park and access could be made from the area near a historic U.S. Borax mining town which is now managed by Rio Tinto’s nonprofit organization.

In another area within view of the White Monster claim and outside of Death Valley National Park, the U.S. Borax exploration department staked mining claims and drilled exploratory holes on the basalt-capped plateau above Rio Tinto’s historic mining town between 1981 and 1996. Thirty-eight years later Rio Tinto continues to own 231 claims and sites from the work performed between 1981 and 1996 and files the annual notice of intent to hold the mining claims and mill sites with the county.

Another area which Rio Tinto continues to hold patented claims are those a short distance to the east of the White Monster patented claim and the 231 claims steaked on the plateau above Rio Tinto’s historic mining town. These are the claims from the workings of the Pacific Coast Borax’s 1907 Lila C mine.

An independent company research and estimated fair value report published April 29, 2019, on Ioneer’s Rhyolite Ridge lithium project by Silver Peak, Nevada, made the following statements about Rio Tinto and Rio Tinto’s U.S. Borax company.

“U.S. Borax is likely to cease production at some point in the next 10 years making Rhyolite Ridge the obvious replacement, especially as it’s a large resource with a long life of mine.”

“Experienced board members: For a midsize company (A$257m) ioneer has a very experienced board and management that includes a number of senior ex Rio Tinto staff. This should prove instrumental in securing ioneer off-take / prepayment contracts for its boric acid production.”

“Two companies essentially control 80% of supply and in the case of U.S. Borax (Rio Tinto operating in Boron, California) its main operating asset is maturing, and costs are rising. Rio Tinto has the Jadar project in Serbia but by all accounts, there is still a substantial amount of feasibility and development work to be done. Originally Jadar was targeting production in 2023 that currently looks highly unlikely. No doubt Rio Tinto will want to replace U.S. Borax, however, Jadar is not likely to be operational within the next 5-8 years.”

Rio Tinto has been active in Serbia since 2001 and discovered the Jadar lithium borate deposit in 2004. Rio Tinto has plans to start production in 2023 if feasibility studies confirm viability and all the necessary approvals are obtained. Rio Tinto has invested and committed more than $200 million on the project through October 2019. Significant investment is required to continue technical analysis and planning before the project can move to construction and operation.

The Australian newspaper reported July 12, 2019, that Rio Tinto is linked to an interest in Ioneer’s Rhyolite Ridge lithium undertakings. Analysts have been examining if major miners such as Rio Tinto might buy into lithium at a time when they are struggling to find production growth opportunities. It is also thought that Ioneer’s Rhyolite Ridge could be too small of a market for Rio Tinto. But Oct. 31, 2019, Reuters reported that Rio Tinto was pivoting toward smaller finds that had growth potential. In another article the Australian Financial Review reported that Rio Tinto CEO Jean-Sebastien Jacques believes the future of mining will be in smaller mines that deliver faster turns on investment. Jacques also said ”In terms of resource development maybe the majors also need to think more like fast moving juniors.”

Nov. 1, 2019, Mining News discusses how Rio Tinto’s intermittent messaging around adding lithium to its portfolio to plug in to the  electric vehicle and renewable energy storage revolution has become increasingly confused and could benefit Ioneer’s Rhyolite Ridge project. “Rio’s lithium muddle and why ioneer could benefit.”


Rio Tinto Borax Mine on Google Maps

Rio Tinto website

Boron, California Operations website


(Please notify author on the website contact page for errors, omissions or suggestions.)


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