Beijing, 20 April (Argus) —

Chinese base metals mining firm Huayu Mining, has launched production at its antimony-gold smelter Talco Gold in Tajikistan following Covid-19-related delays in the last few years.

Huayu and Tajikistan Aluminium, a state-owned aluminium smelter, are co-investors in Talco Gold. The project is expected to process 1.5mn t/yr of ores to produce 2.2 t/yr of gold and 16,000 t/yr of antimony metal when it reaches full capacity. The project was supposed to launch in 2019 but faced delays because of the Covid-19 pandemic.

Tajikistan Aluminium owns 264,616t metal equivalent of antimony and 49.9t of gold resources.

Huayu mines lead, zinc, copper and silver and owns 434,600t metal equivalent of antimony resources in Tibet and outside China after investing in the Talco Gold project. Huayu is able to produce around 5,000 t/yr metal equivalent of antimony metal from its domestic mines.

A continued shortage of concentrate and metal supplies bolstered the antimony market to a 10-year high of 81,500-82,500 yuan/t ($12,800-12,970/t) for 99.65pc grade metal on 24 March. The range softened by Yn500/t from 7 April to Yn81,000-82,000/t ex-works on 12 April as weaker demand outweighed the concentrate shortage to prompt sellers to cut offers to attract sales. Export prices for the metal have remained firm at $14,100-14,300/t fob since 24 March as tight supply outside of China has encouraged Chinese exporters to maintain their offers.

The Chinese antimony market has been rising over the past month, with prices hitting a 10-year-high on 15 March driven by continued shortages of concentrate feedstock availability and supply uncertainty because of the Russia-Ukraine conflict.

Prices for 99.65pc grade antimony metal were last assessed at 80,000-81,000 yuan/t ($12,600-12,760/t) on 15 March, up by Yn8,000/t from 8 February when market participants returned from the lunar new year holiday. Export prices for 99.65pc grade metal were assessed at $13,800-14,000/t fob, up by $200/t fob from 10 March and up sharply by $650/t from a week earlier.

Metal producers have kept lifting their offer prices and are withholding material from sales in response to limited stocks and renewed buying interest.

China produced 35,802t of antimony concentrate in 2021, down by 15pc from the previous year, with it producing 65,661t of antimony metal that was down by 16pc over the same period, according to data from the China Nonferrous Metals Industry Association. Production in the first few months of this year are expected to continue falling because of depleted concentrate resources in China, along with reduced concentrate imports from other countries disrupted by the Covid-19 pandemic and Ukraine-Russia conflict.

China’s January production of antimony metal fell to 7,142t from 8,178t a month earlier and was down from 7,643t a year earlier, with key metal producers in Hunan province reducing production on a lack of concentrate availability. Most private-sector metal producers in the province’s Lengshuijiang city, the largest antimony production hub in China, have yet to reopen their blast furnaces and are maintaining only a few refining furnaces to produce metal. Their refining furnaces are also likely to be closed in April if the concentrate supply shortages continue, according to the producers. The seven producers have a combined metal capacity of 35,000-40,000 t/yr.

The two major antimony producers Hsikwangshan Twinkling Star and Chenzhou Mining have been buying truckloads of metal from private-sector metal producers since late January as they have completed production chains from ore to metal and then to trioxide and downstream products. The two producers have suspended offer prices for metal this week and are prioritising meeting in-house consumption on expectations of further feedstock shortages.

Demand from the domestic downstream alloy and flame retardant industries has remained weak, with most consumers operating from stocks or making purchases for prompt demand because of the consecutive rises in feedstock prices. But antimony suppliers have held firm on their offers in anticipation of renewed demand from downstream consumers after they run out of stocks.

China’s antimony metal output declined in January on the month and on the year as most smelters had to lower production on a persistent shortage of concentrate supplies.

China’s January production of antimony metal fell to 7,142t from 8,178t in December 2021, and was down from 7,643t a year earlier, according to data from the China Nonferrous Metals Industry Association (CNMIA).

Production is likely to fall further in February as most producers cut or halted output during the lunar new year holiday and postponed production restarts on a shortfall of concentrate availability.

Export prices for the metal were assessed at $13,000-13,300/t fob on 1 March, up by $200/t from the assessment on 24 February, in line with higher domestic prices and supply tightness outside of China.

Prices are likely to move up further as many smelters in Hunan province’s Lengshuijiang city, the antimony production hub in China, may shut down metal production if concentrate supplies tighten further on Covid-19 restrictions and the uncertainties brought about by the war between Ukraine and Russia. Russia is a key antimony concentrate supplier and the country exported 38,364t of antimony concentrate during 2020-21, with 68.2pc shipped to China.

China’s antimony production rose during January-September as several producers maintained or lifted output on continued price gains.

Output totalled 78,843t during January-September, up by 20.29pc from the same period in 2020, according to data from the China Nonferrous Metal Industry Association (CNMIA).

September production of 9,666t increased by 12.28pc from 8,609t a year earlier and fell slightly from 9,757t a month previously.

Prices for antimony on 2 November were assessed stable at 66,000-67,000 yuan/t ($10,317-10,474/t) ex-works, following a fall of Yn2,000/t on 28 October, with production restarts in Hunan province’s Lengshuijiang and a slowdown in demand from the flame retardant industry. Almost all smelters in the main production hub of Lengshuijiang restarted production as environmental issues eased.

On the economic front in central Newfoundland, it claimed some 100 mining jobs at the Beaver Brook Antimony Mine, about 40 kilometres outside Glenwood.

However, as things start to rebound in the province the Beaver Brook operation has restarted.

In early September, a statement was published on the Beaver Brook Antimony Mine’s Facebook page that there were plans to restart full operations at the site in late September or early October.

“Meanwhile, we have begun the internal planning and preparations to restart our mine in a safe, efficient, and orderly manner,” read the statement.

What is antimony?

Antimony is a chemical element. It’s in a wide variety of products including lead allloys, a variety of flame-retardent compounds, and some semiconductors.

The mining company anticipates there could be as many as two years’ worth of work at the site with the possibility of more as they plan further antimony exploration in the area.

It was last November when word broke that the mine would be suspending operations while maintaining some staff at the site to monitor things, citing the effects of COVID-19 along with increased winter operational costs. The mine had only just restarted with limited operations in July of 2020.

The mine anticipates hiring over 100 people to fill a variety of positions.

The news of the restart was met with optimism from the provincial government. “It is a positive. It is a good thing,” said Industry, Energy and Technology Minister Andrew Parsons.

The mining industry can be cyclical and the group behind the Beaver Brook mine has maintained constant communication with the provincial government since the announced closure in 2020, Parsons said, adding the company had informed them of the planned fall restart.

During the department’s correspondence, the company informed the province it were aiming to restart operations at the mine this fall.

“It is very exciting,” Parsons said.

The latest announcement continues the up and down history of the Beaver Brook mine. After being closed to close to a decade, the mine was restarted in 2019 after it had secured new financial backing and went back into production.

At that time, it was anticipated the project would operate for three to four years and produce upwards of 160,000 tonnes of materials.

“When things did turn around, we’re just really happy to see this,” said Parsons. “This has a big effect whether it is Glenwood, which is probably the closest central (Newfoundland) community, and just the entire central region, which overall is a hotbed for mining.

“It is creating jobs, it is creating spinoffs, it is creating positivity for the industry, and it has a positive impact on the provincial treasury. So, all in all, this happening is a very good thing.”

While antimony may not be part of the common lexicon, humans have been using this semi-metal for more than 5,000 years.

“For example, the ancient Egyptians and early Hindus used stibnite, which is the major ore mineral for antimony, to produce black eye makeup as early as about 3100 B.C.,” the United States Geological Survey penned in a 2018 report on critical minerals.

While antimony’s cosmetic status has waned over the past five millennia, the metalloid’s ability to resist heat and corrosion, make stronger lead alloys, produce clearer glass for high-tech devices, and store renewable energy has created new uses for the ancient metal.

A wide array of American industries, including the defense and energy sectors, are taking advantage of antimony’s unique properties.

“Today, antimony is used in lead-acid storage batteries for backup power and transportation; in chemicals, ceramics, and glass; in flame-retardant materials; and in heat stabilizers and plastics,” according to the USGS.

Despite having significant reserves of stibnite, the U.S. depends on other countries, primarily China, for more than 80% of its supply of this critical mineral. The balance of American supply comes from recycling and refining concentrates imported from Italy, China, India, and Mexico.

“China continued to be the leading global antimony producer in 2020 and accounted for more than 52% of global mine production,” USGS inked in its 2021 Mineral Commodity Summaries report.

Due to America’s heavy reliance on imports, coupled with antimony’s traditional and emerging applications, USGS recently ranked stibnite as the No. 10 most critical mineral to the U.S. when it comes to supply risk.

Idaho and Alaska have stepped up to meet America’s strategic antimony needs in the past, and host rich deposits of the heat-resisting metal that could help fill current and future critical needs.

War hero

Antimony’s flame and heat resistant properties elevated this metalloid to hero status during World War II.

This is largely due to the lives of countless American troops that were saved during the war by an antimony-based fireproofing compound that was applied to tents and vehicle covers.

When combined with a halogen – fluorine, chlorine, bromine, or iodine – antimony suppresses the spread of flames.

“Antimony is also vital to our military’s effectiveness and has been since it was labeled as crucial to the war effort during World War II,” U.S. Army Major General James (retired) “Spider” Marks penned in a 2020 column published in The Washington Times.

Over the eight decades since the end of World War II, antimony continues to save innumerable lives – from soldiers in the field to babies in the nursery – by lending its flame-resistant properties to mattresses, toys, electronic devices, aircraft, and automobile seat covers.

In addition to its widespread heat-resistance applications, antimony imparts increased hardness and mechanical strength into an alloy known as antimonial lead.

Bullets and shot, bearings, electrical cable sheathing, printing machines, solders, and pewter are among the products made of alloys that contain some amount of antimony.

The most common application for antimonial lead, however, is improving the plate strength and charging characteristics in the lead-acid batteries that have been used to start most internal-combustion-engine vehicles for more than a century.

Antimony is also used to make high-quality glass used by both civilians and soldiers. For example, a small amount of antimony oxide has the ability to remove bubbles and make super-clear glass used to make lenses for binoculars and similar optical equipment, as well as the glass screens of smartphones and other electronic devices.

“Antimony is a key ingredient in communication equipment, night vision goggles, explosives, ammunition, nuclear weapons, submarines, warships, optics, laser sighting, and much more,” U.S. Army Major General Marks wrote.

The majority of this antimony is recycled, which accounts for essentially all of America’s supply of the metal that is not imported.

Molten antimony battery

While lead-acid battery usage is expected to decline as electric motors take the place of ICE engines in the vehicles traveling global highways, antimony is finding its way into new applications in next-generation batteries that can efficiently store electricity at the grid scale.

Known as liquid-metal batteries, this relatively new form of energy storage was developed at the Massachusetts Institute of Technology (MIT) in Cambridge.

Ambri, a battery research and development company born from the liquid metal battery research carried out at MIT, is advancing these large grid-scale batteries to commercial use.

The Ambri battery has a calcium alloy anode, a molten salt electrolyte, and an antimony cathode.

At room temperature, Ambri’s cell is non-conductive and its materials are solid. Once heated to 500 degrees Celsius (932 degrees Fahrenheit), however, the minerals and metals melt and become active. The passing of ions through the electrolyte as the battery charges and discharges keeps the metals molten, eliminating the need for auxiliary heating or cooling.

All these liquids are stored in a single stainless-steel tank without the need for dividers because, like oil and water, they have different densities and do not mix.

Ambri says these batteries are less expensive to manufacture, work in a wider range of climatic conditions, last longer, and are safer than their lithium-ion counterparts.

While such batteries won’t likely be used in vehicles, they could solve the problem of creating durable batteries for storing power from renewable sources such as solar and wind power – electricity that can be delivered to the grid as needed.

“Our technology will fundamentally change the way power-grids operate, increasing the contribution from renewable resources and reducing the need to build traditional power plants,” Ambri says. “Customers will see lower electricity bills and more reliable service.”

TerraScale, a data center development firm that prioritizes sustainability and cybersecurity, is leveraging these advantages through the installation of 250 megawatt-hours of Ambri liquid-metal batteries to store solar energy at its Energos Reno project in Nevada.

“Our data center technology partners are looking forward to deploying Ambri’s technology to enable high-volume, reliable, and resilient energy storage with potentially the lowest levelized cost of storage in the industry,” said TerraScale CEO Danny Hayes.

This is a major step in commercializing Ambri’s energy storage technology and bolstering demand for the antimony that goes into its liquid-metal batteries.

Idaho Stibnite Mine

Many of North America’s richest gold districts also host healthy amounts of antimony, but the latter fire-resistant energy metal is often discarded in favor of the more valuable precious metal. This dynamic, however, reversed at gold mines in Idaho and Alaska when antimony’s strategic value increased during the World Wars.

“During the Second World War, when the U.S. faced a crisis because it didn’t have sufficient antimony of its own – let that be a lesson here – and so it launched the development of the Stibnite Mine in Idaho,” said Chris Ecclestone, a mining strategist with Hallgarten & Co. in London.

From 1941 to 1945, Stibnite Mine produced more antimony and tungsten than any other mine in the U.S. – accounting for 90% of the antimony and 40% of the tungsten produced during this wartime effort.

This Idaho mine has been credited for saving millions of lives and helping to bring World War II to an end.

“In the opinion of the munitions board, the discovery of that tungsten at stibnite, Idaho, in 1942 shortened World War II by at least 1 year and saved the lives of a million American soldiers,” according to the March 7, 1956 U.S. Senate Congressional Record.

The lives saved came at an environmental cost to the Yellow Pine area of Idaho where the Stibnite Mine was located. Perpetua Resources Corp., however, plans to help clean up the environmental legacy of the mine while also producing the antimony critical to the U.S.

“America has the brainpower, spirit of innovation and work ethic to continue to solve some of the world’s toughest problems. However, we lack the minerals and materials we need to bring those solutions to life,” said Perpetua Resources CEO Laurel Sayer. “Perpetua Resources can play a key role in re-establishing domestic antimony production and protecting America’s energy, technology and defense future.”

According to a 2014 prefeasibility study, the Stibnite Mine being permitted by Perpetua would produce 99.85 million lb of antimony, 4.04 million ounces of gold, and 2.07 million oz of silver over a 12-year mine life.

Perpetua hopes to finalize the federal permitting process by the end of this year and begin the work of restoring legacy environmental damage and building a modern era Stibnite Mine in 2022. Commercial production of antimony, gold, and silver from the Idaho mine is expected to begin in 2026.

“There is an exciting opportunity to rebalance antimony supplies away from China and break their stranglehold on the metal,” Ecclestone said.

Century of Alaska antimony

For more than a century, Alaska’s gold districts have been hailed for their potential to host economically viable deposits of antimony.

“It has long been known that stibnite, the sulfide of antimony and the principal source of that metal, is widely distributed in Alaska,” Alfred Brooks penned in a 1917 report, Antimony deposits of Alaska.

Brooks’ early 20th-century investigation identified 67 stibnite occurrences in Alaska, most of which are found in areas famed for their gold – Nome, Fairbanks, and Iditarod.

The first record of primary antimony mining in Alaska was the Sliscovich Mine about 30 miles northeast of the gold rush mining town of Nome.

First opened in 1906, Sliscovich was positioned to provide a domestic source of antimony at the onset of World War I, an event that sparked stibnite mining across much of Alaska.

“WWI created considerable demand for antimony,” James Barker, who investigated much of Alaska’s critical minerals potential while working as a geologist for the U.S. Bureau of Mines, told Data Mine North.

While roughly 100 tons of ore shipped from Sliscovich in 1914 and 1915 contained about 35% antimony, the value of the gold and silver in this ore outweighed the critical mineral.

While Sliscovich and other mines near Nome provided some antimony for America during World War I, larger loads of higher-grade concentrates were sent from mines around Fairbanks, in the state’s Interior region.

“In 1915 antimony ore was mined on four properties in the Fairbanks district at the Scrafford, in Treasure Creek basin; the Stibnite, in Eva Creek basin; the Gilmer, in Vault Creek basin; and at Chatham Creek mine,” Brooks wrote. “All the operations were on a small scale and consisted chiefly of open cuts. The total shipments of stibnite from the district during 1915 were 685 tons, which probably averaged 58% antimony.”

Scrafford, the most prolific of these Fairbanks area stibnite mines, has been estimated to produce 2,700 tons of ore containing greater than 50% stibnite over the years.

Former U.S. Bureau of Mines geologist Barker said the lump antimony mined from this hand operation north of Fairbanks “was sacked and transported by cable tram up to the ridge top and then by horse-drawn wagons into Fairbanks to be shipped south by river steamer.”

Today, this property near Kinross Gold Corp.’s Fort Knox Mine is being explored primarily for its gold potential.

A telegram from General Dwight Eisenhower to the workers at the Stibnite Mine thanking them for supplying the World War II war effort (Click to expand).

The antimony potential found in Alaska trends eastward from Fairbanks and into Canada’s Yukon, where one mine between Haines Junction and Whitehorse produced the critical mineral during the 1960s and veins containing an estimated 700 million lb of stibnite remain.

Much like what Perpetua proposes for the Stibnite Mine in Idaho, antimony recovered from deposits in Alaska or the Yukon will likely be a byproduct of mining the gold these northern mining jurisdictions are best known for.

“Enhanced recovery of antimony from precious metal deposits may represent the most readily available source of antimony if demand were to increase rapidly,” USGS penned in its 2018 critical minerals report.

If molten-salt batteries gain traction for utility-scale storage of renewable energy, more gold miners will likely investigate the potential of producing the critical antimony that often accompanies the precious metal.

China’s antimony metal exports in September moved up both on the month and on the year after a fall in August, with consumers in Europe and Asia replenishing stocks.

China exported 1,270t of the minor metal in September, up from 511t in August and up from 587t a year earlier, customs data show.

Antimony metal exports totalled 8,345t during January-September, up by 21.38pc from 6,875t a year earlier.

Antimony exports rose in September compared with a year earlier, in line with a rise in restocking demand from international consumers.

The country exported 5,750t of antimony in September, up by 57.53pc from 3,650t a year earlier and up by 118pc compared with 2,640t in August, customs data show. January-September shipments were up by 31.02pc to 35,354t from 26,983t in the same period in 2020, with international consumers stepping into the market for restocking in response to supply tightness anticipation. The expectation of supply tightness was brought about by production shutdowns in Hunan’s Lenghsuijiang city, which saw curbs imposed because of environmental protection measures.

Export prices for 99.65pc grade antimony metal were last assessed stable at $12,500-12,700/t fob this week following a fall of $100/t on 28 October when spot prices went down, as production restarts in Lengshuiiang City brought about anticipation that prices would move down on further renewed supply. But firm concentrate and other feedstock costs prevented producers from making further concessions on prices despite a lack of ample demand from the downstream flame retardant industry. The export range for another grade antimony held at $10,700-10,800/t fob this week, in line with stable domestic prices.