37-13 Studying Sulfide Mineralogy to Understand Critical Minerals in the Steeple Rock Mining District, Grant County, New Mexico

Session: Geoscience Research Poster Showcase by 2YC and 4YCU Undergraduate Students

Poster Booth No.: 136

Presenting Author:

Nicolas Hausner

Authors:

Hausner, Nicolas Michael¹, McLemore, Virginia T.², Iverson, Nels³, Beauchaine, Samantha⁴

(1) Geology, Community College of Denver, Denver, Colorado, USA, (2) Geology, New Mexico Tech/NM Bureau of Geology and Mineral Resources, Socorro, NM, USA, (3) Geology, New Mexico Tech/NM Bureau of Geology and Mineral Resources, Socorro, New Mexico, USA, (4) Geology, New Mexico Institute of Mining and Technology, Socorro, NM, USA,

Abstract:

Volcanic-epithermal vein deposits characterize the Steeple Rock Mining District of Southwest New Mexico, a historical source of gold and the critical minerals silver, copper, lead, and zinc. Critical minerals are nonfuel mineral commodities essential to economic and national security that the U.S. largely sources from international supply chains, which are vulnerable to disruption. This study evaluates critical mineral potential in the Steeple Rock Mining District through sulfide-mineral geochemistry from the precious- and base-metal veins of the Carlisle-Center fault zone. To assess critical mineral enrichment in epithermal vein deposits, trace-element geochemistry details the five sulfide mineral phases found in study samples - covellite (CuS), chalcopyrite (CuFeS₂), pyrite (FeS₂), sphalerite (ZnS), and galena (PbS). Sulfide phases are characterized by mineralogy and geochemistry using four methods of analysis: Whole-rock geochemistry; reflected-light petrography; X-Ray diffraction; and electron probe microanalysis (EPMA). Reflected-light petrography and X-Ray diffraction identify sample mineralogy, while whole-rock geochemistry indicates the presence of trace critical minerals. EPMA then measures trace elements within the sulfide minerals. From Steeple Rock’s Center Mine, EPMA measures notable concentrations of (1) silver in covellite and (2) tellurium in galena. Tellurium concentrations reach up to 1,700 ppm within galena, while silver averages 5,100 ppm in rims of covellite surrounding galena. With this, covellite recovery is a worthy prospect as an accessory source of Ag, should mining reopen or expand in the future. This study improves understanding of critical mineral distribution in volcanic-epithermal systems and supports ongoing exploration assessments in the district. Results suggest the Steeple Rock Mining District contains great potential for critical mineral enrichment, particularly of Te and Ag. This work was conducted as part of the Geo-Launchpad internship program, supported by the NSF NGF operated by EarthScope Consortium.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-22425

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