| Basis for focus area |
Alkaline/peralkaline igneous rocks. The focus area includes the Trans-Pecos alkaline belt in Texas, extending into New Mexico. |
| Identified resources |
Identified hafnium, lithium, niobium, REE, thorium, tin, and uranium resource; historical production of barite, copper, fluorite, gold, lead, REE, silver, and tungsten. |
| Production |
Wind Mountain (Cornudas Mountains): Test shipments of nepheline syenite; Round Top: Gold, Ag, Cu, Pb, W, REE, and fluorite produced in some districts in New Mexico, fluorite production in Texas; Gallinas Mountains Mining District: Barite: minor production; Fluorite: approximately 1000 tons produced at Red Cloud; total fluorite from district 2,400 tons. |
| Status |
Past mining. Wind Mountain (Cornudas Mountains): Past exploration for nepheline syenite and REE. Round Top: Current and recent exploration as a heavy REE, Sn, U, Be prospect, drilled and analyzed, but never mined; adjacent Sierra Blanca Mountain is being mined for rhyolite road and rail material. Gallinas Mountains Mining District: Past drilling with active claims. |
| Estimated resources |
Wind Mountain (Cornudas Mountains): Round Top: As of 2014, Measured, Indicated and Inferred resources: 82,165,000 metric tons of ore containing tantalum, thorium, REE, niobium, hafnium, tin, and uranium at 428 g/t Y equivalent. They also estimated a lithium resource from column test at 400+ ppm Li. Gallinas Mountains Mining District: 537,000 short tons of 2.95% total REE (not NI 43-101 compliant; Schreiner, 1993). |
| Geologic maps |
Horton and others (2017), scale 1:500,000. |
| Geophysical data |
Recent high resolution geophysical coverage over Trans-Pecos areas in Texas and Cornudas Mountains in New Mexico. Inadequate aeromagnetic and aeroradiometric coverage elsewhere. |
| Favorable rocks and structures |
Nepheline syenites; Rhyolite domes or laccoliths. |
| Deposits |
Wind Mountains prospect (MRDS dep_id: 10125858), Round Top prospects (MRDS dep_id: 10085039; USMIN Site_ID: TX00005), All American Prospect (MRDS dep_id; 10150332), Conqueror mine (MRDS deo_id: 10101830), Red Cloud (MRDS dep_id: 10150086). |
| Evidence from mineral occurrences |
MRDS; USMIN. |
| Geochemical evidence |
Chemical analyses of Round Top are in Elliott (2018). Grab samples from the Conqueror fluorite mine have 18% fluorite and 6.2% barite (McLemore, 2010c). |
| Geophysical evidence |
Recent Rank 1 aeromagnetic and aeroradiometric data over part of the region (Bultman, 2021). |
| Evidence from other sources |
Mining permits in specific areas. |
| Cover thickness and description |
Deposits may be present at depth in mapped sedimentary rocks or concealed by Cenozoic basin fill. |
| Authors |
Brent A. Elliott, Virginia T. McLemore, Joshua M. Rosera. |
| New data needs |
Alteration mapping, detailed mapping of the plutons and dikes in terms of lithology, geochemistry and mineralogy of the veins; geophysics. |
| Geologic mapping and modeling needs |
Detailed mapping needed in many areas. |
| Geophysical survey and modeling needs |
High resolution aeromagnetic and aeroradiometric survey over areas without Rank 1 data. |
| Digital elevation data needs |
Lidar complete (Texas) or in progress (parts of New Mexico). |
