Sierra County, New Mexico

Shop Sierra County Minerals HERE

Sierra County, New Mexico, lies due south of Socorro County. It’s the home of Truth or Consquences (aka Hot Springs), famed as a hot springs retreat center for decades (click HERE for more information).

The county is also home to a number of picturesque villages and ghost towns, most related to the gold and silver mining rushes of the 1800s, or to historic cattle and ranching operations (click HERE for more information.)

 It is also the home of the first commercial spaceport designed and constructed specifically for commercial (not government) users. It is owned by the State of New Mexico. Tenants of Spaceport America currently include Virgin Galactic, EXOS Aerospace Systems and Technologies, Space X and UP Aerospace. Tours are available by reservation, click HERE for more information.

 

Sierra County is bounded on the east by the mostly N-S trending San Andres Mountains, and on the west by the Black Range. Two major reservoirs, the Elephant Butte and Caballo, lie along the Rio Grande River, roughly in the middle of the county, and paralleling Interstate 25. The frontispiece of George Townsend Harley’s 1934 monograph on the geology and mining districts of Sierra County (above) illustrates the overall landscape.

The geology of Sierra County is similar to that of adjacent Socorro, Dona Ana, and Grant counties. Like much of New Mexico, Sierra County geology reflects a long geologic history of sedimentation in a stable area of the continent (known as the craton), subsequently buried and turned into rock, then modified by tectonism that resulted in magmatic events (intrusion of magma, volcanic eruptions, and mineralization of host rocks), uplift, folding and faulting. These events stretched from what is now Mexico up to Montana producing what are termed porphyry deposits, rich in gold, copper and other valuable mineral resources.

Minerals by District

This list gives all referenced minerals in the literature for each district; many are present only as minor constituents and are not really collectible.  

Black Range Tin District: aegirine, amethyst, analcime, beryl, beudantite, bixbyite, brabantite, calcite, cassiterite, cerianite, chabazite, chalcedony, chernovite, clinopyroxene, cristobalite, cryptomelane, durangite, fluorite, gasparite, goethite, gold, halloysite, hematite, heulandite, hidalgoite, ilmenite, jarosite, kaolinite, magnetite, maxwellite, mesolite, monazite, montmorillonite, mordenite, nagyagite, opal, orthoclase, pigeonite, pseudobrookite, quartz, rutile, sanidine, smectite, squawcreekite, stellerite, stilbite, stolzite, todorokite, topaz, tridymite, vanadinite, wakefieldite 

Caballo Mountains district: aegirine, analcime, anglesite, augite, azurite, barite, biotite, bornite, brannerite, calcite, cerussite, chalcocite, chalcopyrite, chlorite, chrysocolla, clinoenstatite, covellite, cuprite, descloizite, fluorite, galena, glauconite, gold, selenite, hematite, jarosite, kaolinite, limonite, magnetite, malachite, microcline, minium, montmorillonite, mottramite, muscovite, nepheline, olivine, plagioclase, psilomelane, pyrite, pyromorphite, quartz, riebeckite, siderite, silver, spinel, tenorite, uraninite, uranophane, vanadinite, wulfenite

Chloride district: acanthite, amethyst, andesine, anglesite, aragonite, argentite, azurite, barite, betekhtinite, bornite, bromargyrite, calaverite, calcite, cassiterite, celadonite, cerussite, chalcocite, chalcopyrite, chlorargyrite, chlorite, chrysocolla, copper, covellite, cuprite, delafossite, digenite, epidote, fluorite, freibergite, galena, geerite, gold, gonyerite, hematite, jalpaite, limonite, magnetite, malachite, molybdenite, horthoclase, polybasite, proustite,, pyrargyrite, pyrite, pyromorphite, quartz, silver, sphalerite, stromeyerite, sylvanite, tellurium, tenorite, tetrahedrite, todorokite

Cuchillo Negro district: actinolite, albite, anglesite, augite, azurite, brochantite, calcite, cassiterite, cerussite, chalcopyrite, chlorargyrite, clinoptilolite, cuprite, descloizite, fluorite, galena, hematite, hemimorphite, idaite, limonite, linarite, magnetite, malachite, mottramite, orthoclase, pyrite, quartz, ramsdellite, siderite, smithsonite, sphalerite, talc, tremolite, vanadinite, willemite, wulfenite

Derry district: anatase, anglesite, apatite, barite, bastnasite, calcite, chlorite, fluorite, galena, goethite, hematite, limonite, magnetite, microcline, muscovite, orthoclase, plagioclase, psilomelane, pyrite, pyrolusite, quartz, rutile, siderite, spinel, thorite, thorogummite, uraninite, uranophane, zircon

Fra Cristobal district: barite, fluorite, galena, goethite, gypsum, hematite, olivine, quartz

Goodfortune Creek district: bornite, chalcocite, chalcopyrite, covellite, galena, goethite, gold, hematite, jarosite, malachite, pyrite, quartz 

Grandview Canyon district: bismuth, bismuthinite, bismuthite, calcite, chalcocite, chalcopyrite, fluorite, jarosite, labradorite, malachite, molybdenite, pyrite, pyrolusite, quartz, scheelite, vanadinite, wolframite

Hermosa district: acanthite, andesine, anglesite, argentite, azurite, barite, bornite, brochantite, bromargyrite, calcite, celadonite, cerussite chalcotite, chalcopyrite, chlorargyrite, chrysocolla, covellite, cuprite, descloisite, dolomite, epsomite, galena, goethite, gold, gypsum, hematite, lepidocrocite, limonite, malachite, manganite, marcaseite, miagyrite, mimetite, montmorillonite, mottramite, polybasite, psilomelane, pyrargyrite, pyrite, pyromorphite, quartz, silver, smithsonite, sphalerite, stephanite, talc, tetrahedrite, todorokite, vanadinite, wulfenite

Hillsboro district: actinolite, anglesite, apatite, argentite, azurite, biotite, bornite, calcite, cerussite, chalcanthite, chalcocite, chalcopyrite, chlorargyrite, chlorite, chrysocolla, copper, cuprite, descloizite, diopside, epridote, fluorapatite, fluorite, galena, gold, hematite, hemimorphite, heulandite, ilmenite, kaolinite, kentrolite, limonite, magnetite, malachite, massicot, melanotekite, mimetite, minium, molybdenite, mordenite, mottramite, sericite, orthoclase, plagioclase, psilomelane, pyrite, pyrolusite, quartz, rhodochrosite, siderite, silver, smithsonite, sphalerite, tellurium, tetradymite, titanite, tremolite, vanadinite, willemite, wulfenite, zircon

Hot Springs district: ankerite, argentojarosite, barite, biotite, bornite, celestite, chalcopyrite, chert, chlorargyrite, cryptomelane, dolomite, galena, ilmenite, montmorillonite, murdochite, olivine, plumbojarosite, pyrolusite, quartz, uraninite.

Iron Mountain No. 2 district: andalusite, andesine, andradite, anglesite, anorthite, apatite, augite, axinite, beryl, biotite, bismuthinite, bytownite, calcite, cerussite, chamosite, chlorite, clinozoisite, danalite, diopside, epidote, ferrimolybdite, fluorite, galena, gold, graphite, grossular, hedenbergite, helvite, hematite, hemimorphite, kalolinite, labradorite, magnetite, manganite, sericite, opal, orthoclase, ottrelite, piemontite, powellite, pyrite, pyrolusite, pyrrhotite, quartz, rhodochrosite, scheelite, smithsonite, spessartine, sphalerite, spinel, stolzite, tilleyite, tremolite, tungstite, vesuvianite, willemite, wollastonite, wulfenite, zoisite 

Kingston district: acanthite, alabantite, anglesite, aragonite, argenitite, bornite, calcite, cerussite, chalcopyrite, chlorargyrite, cinnabar, cuprite, dickite, dolomite, fluorite, galena, gold, goslarite, hemimorphite, hydrozincite, kaolinite, limonite, malachite, miagyrite, orthoclase, polybasite, proustite, psilomelane, pyrargyrite, pyrite, pyrolusite, pyrostilpnite, quartz, realgar, rhodochrosite, rhodonite, silver, smithsonite, sphalerite, talc, tetrahedrite, todorokite 

Lake Valley district: analcime, ankerite, apatite, argentite, augite, braunite, calcite, cerussite, chlorargyrite, chlorargyrite, cryptomelane, descloizite, fluorite, galena, groutite, gypsum, hematite, iodargyrite, limonite, mallardite, manganite, mottramite, proustite, psilomelane, pyrargyrite, pyrite, pyrolusite, quartz, ramsdellite, scheelite, silver, sphalerite, stephanite, todorokite, vanadinite, wulfenite

Lava Gap district: barite, calcite, fluorite, galena, gypsum

Macho district: anglesite, augite, barite, calcite, cerussite, chlorite, coronadite, descloizite, epidote, galena, hematite, hemimorphite, hypersthene, labradorite, limonite, magnetite, sericite, psilomelane, pyrite, pyrolusite, pyromorphite, quartz, smithsonite, sphalerite, stilbite, tridymite, vanadinite, willemite, wulfenite 

Monticello Tin district: calcite, cassiterite, chevkinite, clinopyroxene, diopside, hematite, maxwellite, pseudobroookite, quartz, sanditine, tilasite, titanite, tridymite, uranophane, zircon

Pittsburg district: anglesite, barite, calcite, chalcocite, fluorite, galena, glauconite, gypsum, hematite, ilmenite, magnetite, microcline, monazite, muscovite, orthoclase, psilomelane, quartz, romanechite

Salinas Peak district: azurite, barite, bismuthinite, bismutite, chalcopyrite, copper, ferrimolybdite, fluorite, galena, greenockite, kaolinite, limonite, malachite, molybdenite, sphalerite, talc

San Mateo Mountains district: carnotite, cassiterite, descloizite, fluorite, gold, limonite, opal, pyrite, quartz, tridymite, tyuyamunite, uraninite, uranophane

Sulphur Canyon district: barite, calcite, chlorite, chrysocolla, fluorite, galena, hematite, malachite, quartz

Tierra Blanca district: acanthite, argentite, azurite, bromargyrite, calaverite, calcite, cerussite, chalcocite, chalcopyrite, chlorargyrite, chlorite, chrysocolla, cuprite, dolomite, fluorite, galena, glauconite, gold, hematite, hessite, limonite, malachite, muscovite, petzite, pyrite, quartz, roscoelite, serpentine, silver, smithsonite, sphalerite, sylvanite, tellurium, tenorite

Willow Creek near Cuchillo: augite, hematite, pseudobrookite, titanite

San Andres Mountains: anhydrite, celestite, cuprotungsite, witherite