According to Mining Weekly, NevGold, which is listed in Toronto, Frankfurt and on the OTCQB, has reported positive results from phase one pit sampling at its Limon Butte project in Nevada, United States. The results confirm the continuity of antimony and gold grades within historic heap leach pads and indicate potential for near-term antimony production.
The historic heap leach pads were constructed during mine operations between 1989 and 1990, when gold prices were below US$400 per ounce and antimony was not a target metal. Historical records indicate that the pads may contain between 2.4 million and 3.0 million tonnes of previously mined material, currently exposed at surface.
Surface sampling conducted by NevGold across two historic heap leach pads demonstrated consistent and relatively high antimony and gold grades. The materials are classified into crushed ore heap leach pads and run-of-mine heap leach pads.
Based on historical data, the crushed ore pads contain approximately 1.4–1.7 million tonnes of material grading 0.72% antimony and 0.43 g/t gold, with particle sizes of approximately one-third of an inch. The run-of-mine heap leach material is estimated at 1.0–1.3 million tonnes, grading 0.31% antimony and 0.81 g/t gold, with variable particle sizes.
NevGold stated that both heap leach pad types show very consistent antimony and gold mineralization, with all sampling pits returning mineralized material. Localized antimony grades range from 0.47% to 0.81%, depending on the sample.
The company noted that recovery of residual antimony and gold from the historic heap leach pads is highly likely. Metallurgical testing conducted at Limon Butte has also demonstrated favorable processing characteristics, with antimony heap leaching identified as a priority approach.
Tests completed last year showed that acid leaching achieved antimony recoveries of up to 92%, with minimal impact on gold recovery. NevGold added that gold remaining in the heap leach pads could be recovered following antimony processing.
Acid leaching is considered the preferred metallurgical method for antimony, as it does not rely on downstream third-party smelters. Under this scenario, antimony metal would be produced on site using conventional leaching and electrowinning, similar to the solvent extraction–electrowinning (SX/EW) process widely used in the oxide copper industry.
Due to its strategic importance and military applications, antimony is classified as a high-risk critical mineral. Limon Butte is a historic Nevada mining district that hosts near-surface, high-grade antimony mineralization.
NevGold stated that the historic heap leach pads enable near-term antimony production, while also supporting the advancement of larger-scale gold and antimony development.
Beyond the heap leach pads, the company is advancing drilling, metallurgical testing and resource estimation preparations at Resurrection Ridge, Cadillac Valley, and the Bullet Zone, a high-grade gold discovery made in 2025.
NevGold noted that a phased development strategy could create multiple development scenarios over the next 12 to 24 months, potentially leading to near-term production and cash flow.
As part of its 2025–2026 work program at Limon Butte, the company has completed a review of its historical geological database with a focus on gold and antimony and has advanced second-phase metallurgical testing. To date, 30 drill holes targeting gold and antimony have been completed.
The company is also advancing near-term antimony production from both crushed and run-of-mine heap leach pads. Following completion of phase one sampling and metallurgical work, sonic drilling has commenced, and preliminary gold-antimony resource estimation is underway.
“These results rapidly reduce risk and significantly increase the probability of near-term production at Limon Butte,” said NevGold CEO Brandon Bonifacio. “The project represents a near-term brownfield development opportunity, with large volumes of previously mined material already exposed at surface.”
“By adding antimony, multiple development scenarios become possible and are currently being evaluated. We believe this represents one of the near-term opportunities to build an integrated upstream and downstream antimony supply chain in the United States.”
“While advancing the historic heap leach pads, we are also progressing drilling, metallurgical testing and gold-antimony resource estimation at Resurrection Ridge, Cadillac Valley and the Bullet Zone, supporting the development of a larger-scale commercial gold-antimony operation. This provides significant optionality for advancing Limon Butte into production and generating cash flow,” Bonifacio added.
[出处 – 上海有色网] 美国利蒙峰金锑矿勘探和再利用进展 https://news.smm.cn/news/103708895
