Horse Heaven Antimony Project
OVERVIEW
The Horse Heaven Antimony-Gold-Tungsten Project is well-situated in Valley County, Idaho USA, sharing its eastern boundary with Nasdaq-listed Antimony giant Perpetua Resources’ (~A$2 billion market cap) Stibnite Gold Project. Stibnite hosts a 4.8M ounce Gold reserve and a significant endowment of Antimony and tungsten.
The Horse Heaven Project comprises 699 federal lode mining claims covering over 5,644 hectares and is home to a number of past-producing Antimony, Tungsten and gold mines. The project has several high-priority target areas, including the Golden Gate & Antimony Ridge prospects. Shallow historical drilling has confirmed mineralisation from surface.
The project is close to the town of Cascade, Idaho, and important infrastructure, which is being upgraded to support the development of the Stibnite Mine.
ADJACENT TO STIBNITE ANTIMONY GOLD PROJECT
Horse Heaven shares its eastern boundary with Perpetua Resources’ Stibnite Gold Project. Due to its high grade and low strip ratio, Stibnite is set to become one of the largest high-grade, low-cost gold mines in the USA and the only domestic source of antimony. Stibnite boasts 6M oz of Measured & Indicated gold reserves, with antimony and tungsten being “by-products.”
It also has a solid history of gold antimony production, having yielded over 980,000 oz of gold, 13.5M pounds of tungsten, and 88M pounds of antimony at Stibnite during WWII and the Korean War, accounting for 90% of total US antimony production at the time.
Antimony Ridge Prospect
High-grade Antimony was produced from small open pits at the Antimony Ridge Prospect during the periods of World War I, World War II, and into the early 1950s, confirming significant potential to host Antimony deposits. Historical trenching has also identified a 500m Antimony-Gold-silver mineralisation trend at the prospect.
Golden Gate Prospect
The Golden Gate Prospect has a historical, non-JORC code compliant gold resource of 216,000 ounces of gold in 7,256,800 tons of material at a grade of 0.93g/t at Golden Gate Hill, and gold resource of 70,000 ounces of gold in 3,174,850 tons of material at a grade of 0.69g/t at Antimony Hill. From the 1950s up to 1980's approximately 8000 tons of tungsten was mined at the prospect.
WHY ANTIMONY?
Antimony is an indispensable mineral in many modern industrial and technological applications
These include defence industries, where its unique properties are harnessed for a range of military applications. It is used to harden lead in bullets and shrapnel, and is a key component in armour-piercing projectiles and artillery primers. The element is also essential in the production of night vision goggles and infrared sensors, making it indispensable for surveillance technologies. It's also heavily relied upon in the technology sector, where antimony is found in everything from circuit boards and semiconductors to electrical switches and fluorescent lighting. Its ability to enhance conductivity and flame resistance makes it ideal for precision electronics. Additionally, it is used in the production of high-quality clear glass, vital for both consumer and industrial applications.
Antimony is also becoming increasingly important in the clean energy transition. It is used in copper wiring insulation and is a critical component in both lead-acid and next-generation liquid-metal batteries. Its applications extend to solar panel manufacturing and wind turbines, helping store and distribute renewable energy efficiently.
However, despite the fact that antimony is essential to the USA’s national security and economic vitality, China, Russia and Tajikistan control 90% of the world’s supply. There is currently no US domestic production of Antimony, creating a significant national defence issue.
WHY TUNGSTEN?
Tungsten is classified as a critical metal by multiple U.S. government agencies due to its vital role in national defense and high-performance technologies.
Its exceptional hardness and high melting point make it indispensable for military applications, including tank armor, armor-piercing artillery, rifle ammunition, and emerging hypersonic weapons systems.
Beyond defense, tungsten’s durability and density make it essential for heavy-duty industrial use. It is used in rocket equipment, construction and drilling tools, automotive engine components, and as a wear-resistant alloy in harsh environments where strength and heat resistance are paramount.
Tungsten is also an important material in advanced electronics and clean technologies. It plays a role in battery technology, semiconductors, and equipment for vehicle production. Its ability to conduct electricity and withstand high temperatures makes it ideal for circuit boards, power supply units, lighting systems, and shielding in X-ray and radiation applications.
However, there is a looming supply crunch due to a lack of domestic production in the United States. Currently, most tungsten mining and processing occurs in China, followed by Vietnam, Russia, North Korea, Bolivia, and Spain—raising concerns about supply chain security for this strategically vital metal.
