Two weeks ago, Sterling Metals $SAG released their second round of drill results from its Sail Pond Project in northwestern Newfoundland. The project is primarily focused on trying to discover silver, copper, lead, and zinc within a 9km geological structure believed to contain a large network of quartz veining.  The Oct. 7th results were Sterling’s best so far, including one intercept of just under one-half a meter with 1572 g/t of silver, 5.84% copper, 7.8% lead, and 29% zinc.  Although this particular intercept was not particularly thick, it wasn’t an isolated zone. There were other quartz zones possessing good mineralization. Sterling’s pitch all along has been that Sail Pond needs to be looked at as a system, not individual deposits.   So far, the few drill results released provide evidence of numerous capillaries of mineralized quartz intrusions. I am hopeful that as Sterling continues releasing results from its 8,500m drilling program that it will show a move from the capillaries into the larger veins that fed the capillaries as the system was being formed.

Hopefully the improvement from the first batch of results to the second batch are the start of a positive trend as Sterling continues to release more assay results (last I heard, at least 6,000 of the 8,500 meters has been drilled and results should keep trickling in over the next few months). In these most recent drill results, there was one thing that jumped out at me as particularly interesting. Within its highest-grade intercept, Sterling reported that the section of core contained 2.47% antimony.

Antimony?!?! I am willing to guess that most people haven’t heard of or know much about antimony, and some might even mistake it for what a person is ordered to pay an ex-spouse after a divorce. In actuality, antimony is a rare but critically important element for numerous reasons.

What is #antimony and how is it used?

Antimony is an element identified on the periodic chart with the symbol Sb. It has an atomic number of 51 and falls within a small number of elements that are classified as metalloids, along with boron, silicon, germanium, arsenic, and tellurium. The class of metalloids sit right at the boundary line on the periodic chart between the metals and non-metals. One thing that is interesting about metalloids is that they actually possess properties of both metals and non-metals, but they don’t definitively fall into either classification. The name antimony actually comes from the Greek roots ‘anti’ and ‘monos’ meaning “not found alone” or “against aloneness.” This is actually quite important because the real significance of antimony is its use as a metal alloy.  As a sidebar, I haven’t seen anything stating definitively whether the antimony found at Sail Pond is in the common form of stibnite (Sb2S3) or a unique and rare natural silver alloy pyragyrite (Ag3SbS3) which manifests with a dark red gemstone appearance (but that would be cool to get my hands on if it is!).

For many years, antimony was used as a hardener for lead, steel and tin. Today, antimony has numerous additional uses which make it such a critical resource. One of the reasons there are so many new applications using antimony is that while being a weak electrical conductor, antimony has a high charge mobility (how fast a charge moves through a material) as well as a very low thermal conductivity. As we have moved to a silicon-based economy, a conductive material that can handle high heat without suffering degradation has become more and more important. In fact, researchers at the University of Texas are currently working on next-generation processor chips utilizing antimony instead of silicon that have so far shown very promising results due to antimony’s ability to maintain a high charge mobility even while being only a few atomic layers thick.

Antimony also has key applications in clean energy development. Antimony is used in solar panels (as it is able to create a thin clear layer over glass without causing discoloration), wind turbines, generators, and nuclear reactors because of its thermal and electric conductivity properties.

Another new and exciting use of antimony is in next generation battery systems. Ambri, a company partially-funded by Bill Gates has developed a battery system that utilizes liquid calcium alloy as the anode, antimony as the cathode, and a molten salt as the electrolyte. An Ambri battery system with a capacity of 250MWh is being integrated into TerraScale’s Energos Reno project that began construction this year. And Ambri isn’t the only company that is developing non-flow batteries as an alternative to lithium batteries that currently dominate the market. Similar battery systems (all utilizing antimony) are also being developed by Eos Energy Systems and 24M. If performance of these battery systems continues as expected, it should result in a major increase in demand for antimony.

All these green tech uses of antimony are exciting, but there is one overriding reason why preserving antimony supplies and production has become such a key political issue - antimony has crucial military applications. Development of green tech is one thing, but nothing motivates governments like national security interests. Antimony has long been used as a hardener for munitions (i.e. armor-piercing bullets) as it is used in the creation of tungsten steel. Additionally, antimony is a key element used for manufacturing precision optics including night-vision goggles, laser targeting systems, and infrared sensors. Antimony is also used in fire retardant military clothing. All of these military applications explain why US Army Major General James Marks penned a 2020 op-ed piece in the Washington Times urging the resumption of antimony mining in the US in order to “strengthen the supply chain for critical products our defense and energy industries produce.”

Why is the antimony supply chain a concern for Canada, the US and others?

The British government has listed antimony as the number two highest priority critical element or element group since 2015. The Canadian and US governments have included antimony on their Critical Elements lists for a number of years with Canada classifying antimony as “essential to [its] economic security” and US President Joe Biden issuing an executive order in February 2021 that included antimony among the elements whose supply chain “ensures our economic prosperity and national security.”

Unfortunately, more than 80% of the current worldwide antimony supply comes from China and Russia. Although the US gets about 14% of its antimony from recycled sources, it is otherwise entirely dependent on imported sources of antimony with 72% coming from China and India. I was unable to find similar statistics for Canada, but I assume it is similar to the US. There are no active antimony mining operations in the United States although there is an ongoing attempt to restart mining operations at the Stibhite Gold Project in Idaho. This still appears to be several years away from being recommissioned. There is only one active antimony mining operation in Canada, the Beaver Brook Mine. The Beaver Brook Mine is located adjacent to New Found Gold’s $NFG Queensway project and sits adjacent to the Dog Bay Line on the west. Beaver Brook is owned and operated by Chinese Hunan Non-Ferrous Metals (CHNM) and all the ore mined at Beaver Brook is exported to ingot producers in India, Vietnam and Oman. As a side note, the proximity of Beaver Brook Mine to Queensway does pique my interest as to whether New Found Gold will also find viable deposits of antimony as it continues exploration closer to the Dog Bay Line… but I digress.

The lack of any active mining operation other than the Chinese-owned Beaver Brook Mine, leaves Canada and the United States with no current domestic antimony production and neither country possesses a current stockpile of antimony in the event of a complete supply disruption. So what has happened to the price of antimony recently? Unsurprisingly, the price has nearly doubled in 2021, with a current price of approximately $5.45/lb. With several new applications in which antimony is being used, it is expected that increasing demand will lead to ongoing upward pricing pressure.

How Might this Impact Sterling Metals?

While antimony is certainly not the primary motivation for Sterling Metals’ exploration at Sail Pond, the presence of high-grade antimony in its drill results is still intriguing. It is important to remember that Sterling is just getting started with the exploration of Sail Pond and I am fairly confident that as drilling and other geological analyses continue, their targeting will move from the capillary quartz boundaries they are currently hitting into the larger quartz vein systems that fed those capillaries. So far, there has been a strong correlation in their drill results that as overall mineralization of silver, copper and zinc has increased so has the concentration of antimony. This makes me optimistic that we may be seeing even higher grades of antimony in the future as the grades of silver, copper, lead and zinc also improve.

So while the presence of antimony in its drill results don’t change the fundamentals of what Sterling is trying to do with its business plan, future antimony concentrations are something I plan to keep my eye on. While I try to avoid catastrophizing things, it is not too hard to imagine a scenario where geopolitical tensions between the US/Canada and China/Russia quickly escalate resulting in major disruptions to the antimony supply chain. If that were to occur, there would be tremendous political pressure to quickly secure access to antimony from known North American sources. With few known economically viable sources in North America, it is certainly possible that Sterling could be a major beneficiary in such a scenario. While that scenario remains unlikely, due to the implications on military readiness, future antimony results are still something I will be interested in seeing as Sterling continues to release results from its summer drilling program.