Scheelite (CaWO₄) specimen fluorescing bright blue under shortwave ultraviolet illumination. Scheelite’s intense blue response is caused by intrinsic activation within the mineral lattice, distinguishing it from most fluorescent minerals whose glow results from trace impurities. This mineral naturally occurs and serves as a main source of tungsten.
Niki Wintzer, PhD
Niki is a Research Geologist in the Geology, Minerals, Energy, and Geophysics Science Center. In 2007, she joined the USGS in Menlo Park, CA but now works in Spokane, WA. She earned a B.S. in Earth Sciences from California Polytechnic State University in 2004, an M.S. in Geology from San Jose State University in 2009, and her Ph.D. in Geology from Washington State University in 2019.
With specialized skills in geochronology, geochemistry, and structural geology, Niki investigates nationally important ore deposits. The Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho is her current research focus, and it holds the largest resource of the nationally critical commodity antimony. She is constraining the age of tungsten and antimony mineralization, unique geochemical signatures in the ore host rocks, and the ore-controlling structural setting that all provide insight into why mineralization formed when and where it did.
Science and Products
Antimony In and Around the Yellow Pine Deposit, Central Idaho
Project objectives are to document the origin of the Yellow Pine gold-antimony deposit and, by extension, the origin of this deposit type. Our goal is to understand the structural, tectonic, and magmatic setting of the deposit, the character of the ore-transporting fluids, the conditions of ore deposition, and the regional stratigraphic framework and geochemical ore controls of metasedimentary...
Scheelite under shortwave ultraviolet light
Scheelite (CaWO₄) specimen fluorescing bright blue under shortwave ultraviolet illumination. Scheelite’s intense blue response is caused by intrinsic activation within the mineral lattice, distinguishing it from most fluorescent minerals whose glow results from trace impurities. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite under room light
Scheelite (CaWO₄) is pictured here under regular lighting, revealing its typical honey-orange crystal formation atop a paler host rock. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite (CaWO₄) is pictured here under regular lighting, revealing its typical honey-orange crystal formation atop a paler host rock. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite specimen photographed under two lighting conditions
Scheelite specimen photographed under two lighting conditionsScheelite (CaWO₄) is a major tungsten ore. The before/after comparison shows a scheelite specimen photographed under two lighting conditions. In normal room light, the mineral appears orange against its pale matrix, highlighting its crystal form.
Scheelite specimen photographed under two lighting conditions
Scheelite specimen photographed under two lighting conditionsScheelite (CaWO₄) is a major tungsten ore. The before/after comparison shows a scheelite specimen photographed under two lighting conditions. In normal room light, the mineral appears orange against its pale matrix, highlighting its crystal form.
An open pit within the gold-antimony-tungsten mining area
An open pit within the gold-antimony-tungsten mining areaAn open pit within the Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
An open pit within the gold-antimony-tungsten mining area
An open pit within the gold-antimony-tungsten mining areaAn open pit within the Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at Yellow Pine/Stibnite mining area, central Idaho
Geologist conducting field work at Yellow Pine/Stibnite mining area, central IdahoUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at Yellow Pine/Stibnite mining area, central Idaho
Geologist conducting field work at Yellow Pine/Stibnite mining area, central IdahoUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at the gold-antimony-tungsten mining area
Geologist conducting field work at the gold-antimony-tungsten mining areaUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at the gold-antimony-tungsten mining area
Geologist conducting field work at the gold-antimony-tungsten mining areaUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Stibnite Mineral Specimen
Specimen of stibnite, an ore mineral of antimony. Antimony compounds help to prevent skin burns, increase battery life, and refine the glass used in cell-phone screens.
Specimen of stibnite, an ore mineral of antimony. Antimony compounds help to prevent skin burns, increase battery life, and refine the glass used in cell-phone screens.
Science and Products
Antimony In and Around the Yellow Pine Deposit, Central Idaho
Project objectives are to document the origin of the Yellow Pine gold-antimony deposit and, by extension, the origin of this deposit type. Our goal is to understand the structural, tectonic, and magmatic setting of the deposit, the character of the ore-transporting fluids, the conditions of ore deposition, and the regional stratigraphic framework and geochemical ore controls of metasedimentary...
Scheelite under shortwave ultraviolet light
Scheelite (CaWO₄) specimen fluorescing bright blue under shortwave ultraviolet illumination. Scheelite’s intense blue response is caused by intrinsic activation within the mineral lattice, distinguishing it from most fluorescent minerals whose glow results from trace impurities. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite (CaWO₄) specimen fluorescing bright blue under shortwave ultraviolet illumination. Scheelite’s intense blue response is caused by intrinsic activation within the mineral lattice, distinguishing it from most fluorescent minerals whose glow results from trace impurities. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite under room light
Scheelite (CaWO₄) is pictured here under regular lighting, revealing its typical honey-orange crystal formation atop a paler host rock. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite (CaWO₄) is pictured here under regular lighting, revealing its typical honey-orange crystal formation atop a paler host rock. This mineral naturally occurs and serves as a main source of tungsten.
Scheelite specimen photographed under two lighting conditions
Scheelite specimen photographed under two lighting conditionsScheelite (CaWO₄) is a major tungsten ore. The before/after comparison shows a scheelite specimen photographed under two lighting conditions. In normal room light, the mineral appears orange against its pale matrix, highlighting its crystal form.
Scheelite specimen photographed under two lighting conditions
Scheelite specimen photographed under two lighting conditionsScheelite (CaWO₄) is a major tungsten ore. The before/after comparison shows a scheelite specimen photographed under two lighting conditions. In normal room light, the mineral appears orange against its pale matrix, highlighting its crystal form.
An open pit within the gold-antimony-tungsten mining area
An open pit within the gold-antimony-tungsten mining areaAn open pit within the Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
An open pit within the gold-antimony-tungsten mining area
An open pit within the gold-antimony-tungsten mining areaAn open pit within the Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at Yellow Pine/Stibnite mining area, central Idaho
Geologist conducting field work at Yellow Pine/Stibnite mining area, central IdahoUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at Yellow Pine/Stibnite mining area, central Idaho
Geologist conducting field work at Yellow Pine/Stibnite mining area, central IdahoUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at the gold-antimony-tungsten mining area
Geologist conducting field work at the gold-antimony-tungsten mining areaUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Geologist conducting field work at the gold-antimony-tungsten mining area
Geologist conducting field work at the gold-antimony-tungsten mining areaUSGS geologist Niki Wintzer conducting field work at Yellow Pine/Stibnite gold-antimony-tungsten mining area in central Idaho.
Stibnite Mineral Specimen
Specimen of stibnite, an ore mineral of antimony. Antimony compounds help to prevent skin burns, increase battery life, and refine the glass used in cell-phone screens.
Specimen of stibnite, an ore mineral of antimony. Antimony compounds help to prevent skin burns, increase battery life, and refine the glass used in cell-phone screens.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government