May 17, 2020

Stillwater Mining: Only US Producer of Platinum Group Metals (PGM's)

Stillwater Mining
Canadian Mining
J-M Reef
6 min
Stillwater Mining: Only US Producer of Platinum Group Metals (PGM's)
Mining Global takes a look at Stillwater Mining Company

About Stillwater Mining:Only US Producer of Platinum Group Metals (PGM's)

Stillwater Minin...

Mining Global takes a look at Stillwater Mining Company

About Stillwater Mining: Only US Producer of Platinum Group Metals (PGM's)

Stillwater Mining Company is the only U.S. producer of platinum group metals (PGMs) and the largest primary producer of PGMs outside of South Africa and the Russian Federation. PGMs are rare precious metals used in a wide variety of applications, including auto catalysts, fuel cells, hydrogen purification, electronics, jewelry, dentistry, medicine and coinage. Stillwater Mining Company is engaged in the development, extraction, processing, smelting and refining of PGMs from a geological formation in southern Montana known as the J-M Reef and from the recycling of spent catalytic converters. The J-M Reef is the only known significant source of PGMs in the United States and the highest-grade PGM resource in the world.

The Company conducts mining operations at its Stillwater and East Boulder mines in southern Montana. Concentrating plants are located at both mines to upgrade ore to a concentrate. The Company operates a smelter, refinery and laboratory at Columbus, Montana to further upgrade the concentrate to a PGM-rich filter cake. Another key segment of the Company’s operations is the recycling of spent catalyst material to recover PGMs.

The Company owns the Marathon PGM-copper deposit in Ontario, Canada, and the Altar porphyry copper-gold deposit located in the San Juan province of Argentina.

Stillwater Mining Company’s current mining operations are in south-central Montana where it operates two underground mines along the J-M Reef, the world’s richest known deposit of platinum group metals (PGMs).

The Stillwater Complex, which hosts the J-M Reef ore deposit, is located in the Beartooth Mountains in south-central Montana. It is situated along the northern edge of the Beartooth Uplift and Plateau, which rise to elevations in excess of 10,000 feet above sea level. The plateau and Stillwater Complex have been deeply incised by the major drainages and tributaries of the Stillwater and Boulder Rivers down to elevations at the valley floor of approximately 5,000 feet.

Geologically, the Stillwater Layered Igneous Complex is composed of a succession of ultramafic to mafic rocks derived from a large complex magma body emplaced deep in the Earth’s crust an estimated 2.7 billion years ago. The molten mass was sufficiently large and fluid at the time of emplacement to allow its chemical constituents to crystallize slowly and sequentially, with the heavier mafic minerals settling more rapidly toward the base of the cooling complex. The lighter, more siliceous suites crystallized more slowly and also settled into layered successions of norite, gabbroic and anorthosite suites. This systematic process resulted in mineral segregations being deposited into extensive and uniform layers of varied mineral concentrations.

The uniquely PGM-enriched J-M Reef and its characteristic host rock package represent one such layered sequence. The geosciences community believes that the PGM-enriched suite and other minerals characterizing the J-M Reef accumulated at the same time and by the same mechanisms of formation as the rocks enclosing them. Over time, the orientation of a portion of the original horizontal reef and layered igneous complex was faulted an estimated 20,000 feet to the northeast and was tilted upward at angles of 45 to 90 degrees to the north by the Beartooth Uplift. Localized faulting and intrusive mafic dikes are also evident along the 28-mile strike length of exposed Stillwater Complex. The upper portion and exposed edge of the reef complex were eroded, forming the lenticular-shaped surface exposure of the Stillwater Complex and J-M Reef package evident today.

The J-M Reef package has been traced at its predictable geologic position and with unusual overall uniformity over considerable distances within the Stillwater Complex. The surface outcrops of the reef have been examined, mapped and sampled for approximately 28 miles along its east-southeasterly course and over a known expression of over 8,200 feet vertically. That predictability of the J-M Reef has been further confirmed in subsurface mine workings of the Stillwater and East Boulder Mines and by over 38,000 drill hole penetrations.

The PGMs in the J-M Reef consist primarily of palladium, platinum and a minor amount of rhodium. The reef also contains significant amounts of iron, copper and nickel, and trace amounts of gold and silver.

Stillwater Management Team

Michael J. McMullen - President and Chief Executive Officer

Mick McMullen is President and Chief Executive Officer and a member of the Board of Directors. Mr. McMullen was elected to the Board on May 2, 2013 and appointed President and Chief Executive Officer on December 3, 2013. Previously, Mr. McMullen served in a variety of senior executive and directorship positions, most recently as a Principal at MRI Advisory AG, a private company focusing on the development of metal and minerals projects in the Americas, Europe and Africa. Over the course of his 21-year career, Mr. McMullen has been responsible for the development of several large open pit and underground mines in Australia, Europe and Latin America. He has had detailed involvement in all aspects of the mining business, including exploration, permitting, mine development, financing, operations, product sales, and asset acquisition and divestments, as well as the debt and equity markets. He has managed multiple operations across several jurisdictions, working with large work forces and unions in culturally diverse and environmentally sensitive areas. His experience covers a range of commodities including copper, gold, iron ore and PGM’s. Mr. McMullen holds a Bachelor of Science degree in Geology from Newcastle University in New South Wales and pursued graduate studies in Mineral Economics at Western Australian School of Mines.

Dee L. Bray - Vice President, Mine Operations

Dee L. Bray was appointed Vice President of Mine Operations effective March 2015. Mr. Bray joined Stillwater Mining Company in 1994. While working at each of the Company’s Montana Mines, (Stillwater Mine, 12 years and East Boulder Mine, 6 years) he gained experience in engineering, operations, maintenance and safety. He held various engineering and operations positions of increasing responsibility, including Production General Foreman, Safety Manager, Maintenance Superintendent, Production Superintendent and Mine Manager. Prior to his current role, Mr. Bray served as the Manager of Operations, Montana Mines since 2013. 

Mr. Bray began his career with Consolidation Coal Company, working in engineering and operations roles at two underground mines. He has over 27 years of experience in the mining industry, including coal and hard rock.

Mr. Bray earned a Bachelor of Science degree in Mining Engineering from the Montana College of Mineral Science & Technology. He has been a Certified Mine Safety Professional since 2009.

Gregory K. RosetVice President and General Manager, Smelting and Recycling Operations

Gregory K. Roset was appointed Vice President, Smelting and Recycling Operations, effective August of 2010. He has been the General Manager of Smelting since 2001. Mr. Roset joined the Company in 1988 as Concentrator Metallurgical Engineer at the Stillwater Mine, prior to being assigned to the smelter design, permitting and commissioning team in 1989. He has held various technical and managerial positions of increasing responsibility in the smelting operations since 1990. Prior to joining Stillwater, Mr. Roset held various metallurgical and supervisory positions with ASARCO and Kennecott from 1982 to 1988. Mr. Roset is Chairman of the Board of Governors for the Center for Advanced Metals and Minerals Processing at Montana Tech in Butte, Montana. Mr. Roset received both Bachelor of Science and Master of Science degrees in Metallurgical Engineering from the Montana College of Mineral Science & Technology.

Stillwater Mining Company’s corporate office is located in Denver, Colorado.

Source: Stillwater Mining Website -

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Apr 19, 2021

AngloGold Ashanti establishes BG Umoja JV in Tanzania

Daniel Brightmore
3 min
AngloGold Ashanti, Geita, Tanzania, BG Umoja
AngloGold Ashanti’s BG Umoja JV has been awarded a $186mn two-year contract for the Nyankanga and Geita Hill underground mining projects in Tanzania...

AngloGold Ashanti, in line with it s strategy to ensure a sustainable contribution to the economies of host countries, has established the BG Umoja joint venture (JV), in Tanzania.

Awarded a $186m two-year mining contract for the Nyankanga and Geita Hill underground mining projects, the 80/20 joint venture is a partnership between Africa Underground Mining Services (AUMS) Tanzania, a subsidiary of Australia’s Perenti Group, and local drilling services and mining- supply company, Geofields Tanzania Limited. 

The partnership is modelled on a similar underground mining joint venture at the Company’s Obuasi Redevelopment Project in Ghana between AUMS Ghana and Accra-based, wholly Ghanaian-owned Rocksure and will help build local specialised mining capacity.

AngloGold Ashanti

“We’re working with our experienced mining contractors to assist in establishing local joint ventures for long-term transfer of sustainable skills, and to continue building on our sustainable local procurement programmes,” commented Sicelo Ntuli, AngloGold Ashanti’s Chief Operating Officer: Africa. 

“AngloGold Ashanti is building sustainable local procurement programmes that will allow it to stimulate economic and social development at all of its operations, evidenced by the significant contribution Geita has made to the fiscus and people of Tanzania.”

AngloGold Ashanti’s annual expenditure with indigenous Tanzanian suppliers has almost tripled to $162mn since 2016. The company’s local team in Tanzania has set itself an ambitious target of 60% to 70% of all expenditures with indigenous Tanzanian companies, by 2025.

Scope 3 Emissions

In addition, AngloGold Ashanti’s Geita Gold Mine has awarded a two-year fuel transportation contract, worth approximately $10.8m a year, to two local contractors - one of which is originally from Geita. This is in line with the mine’s commitment to contribute to the economies of host communities. The Geita-based company was part of Geita Mine’s supply chain capacity building initiative for host community suppliers, a partnership between the Mine and the National Economic Empowerment Council.

To influence Scope 3 emissions, trucks are to be compliant with EURO IV emissions standards, tankers are to be made of an aluminium alloy material to reduce weight and the age of the fleet will be maintained at less than six years.

Diversity & Inclusion

The contractors already employ women fuel tanker drivers, fulfilling the Mine’s requirements for diversity and inclusion. The two contractors both own workshop facilities in Geita town and participate in social initiatives aimed at uplifting the lives of host community residents.

AngloGold Ashanti has been operating at Geita Gold Mine for more than 20 years, with the project initially a single pit mine, evolving now to a predominantly underground operation, employing 5,700 employees and contractors.

Earlier this year, the Government of Tanzania recognized AngloGold Ashanti’s contribution to the economy of the country, awarding it for its outstanding performance in a number of areas, including environmental and safety performance, corporate social investment, the best taxpayer in the mining sector, the runners up in local business content and overall best performer in the mining sector in Tanzania in 2019/2020.

Geita Gold Mine

Geita, one of AngloGold Ashanti’s flagship mines, is located in north-western Tanzania in the Lake Victoria goldfields of Mwanza region, about 120km from Mwanza and 4km west of the town of Geita. It has been in operation as a large-scale mine since 2000.

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