The USGS Denver Microbeam Laboratory provides chemical analysis and characterization of rocks, minerals, and environmental samples in support of a wide variety of USGS projects related to mineral resources, including research projects funded by the USGS Mineral Resources Program. The research applications for these projects range from mineral resource research and assessments, to geologic mapping and geochronology, to geologic hazards and radioactive waste disposal, to the environment and human health.
Additional Information
For additional information on the laboratory facilities and equipment, visit the Denver Microbeam Laboratory site.
The Denver Microbeam Laboratory has provided support to these Mineral Resources Program projects:
Uranium Mineral Systems
Integrated Hyperspectral, Geophysical and Geochemical Studies of Yellowstone National Park Hydrothermal Systems
Development of USGS Geochemical Reference Materials
Isotope and Chemical Methods for Mineral and Geoenvironmental Assessments and Support of USGS Science Strategy
National Geochemical Database
Non-Traditional Stable Isotopes
Critical Elements in Carbonatites: From Exploration Targets to Element Distribution
Argon Geochronology
Sediment-Hosted Copper Deposits in the Lake Superior Portion of the Midcontinent Rift System
Trace Metal Mobility in the Yellow Pine Mining District, Idaho
Iron Oxide-Copper-Cobalt-Gold-Rare Earth Element Deposits of Southeast Missouri—From the Ore Deposit Scale to a Global Deposit Model
USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response
Below are data or web applications associated with this project.
Table of Electron Probe Microanalyses of Native Copper and Sulfide Minerals from the White Pine Sediment-hosted Copper Deposit, Michigan
Table of Electron Probe Microanalyses of Cassiterite from the Sullivan Pb-Zn-Ag Deposit, British Columbia
Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA
U-Pb data for inherited cassiterite in "Tin Granites", an example from the Yazov Granite, Eastern Siberia
U-Pb data for Origin of Tin Mineralization in the Sullivan Pb-Zn-Ag Deposit, British Columbia: Constraints from Textures, Geochemistry, and LA-ICP-MS U-Pb Geochronology of Cassiterite
Geochemical and mineralogical analyses of uranium ores from the Hack II and Pigeon deposits, solution-collapse breccia pipes, Grand Canyon region, Mohave and Coconino Counties, Arizona, USA
Tables of electron probe microanalyses from the Copperwood sediment-hosted stratiform copper deposit, Michigan, USA
U-Pb data for: Monazite and cassiterite U-Pb dating of the Abu Dabbab rare-metal granite, Egypt: Late Cryogenian metalliferous granite magmatism in the Arabian-Nubian Shield
Geochemical data supporting a comparison of apatite between regional magmatism and the Pea Ridge Iron Oxide-Apatite-Rare Earth Element (IOA-REE) and Boss Iron Oxide-Copper-Cobalt-Gold-REE Deposits (IOCG) deposits, southeastern Missouri, USA
Data Dictionary for Electron Microprobe Data Collected with Probe for EPMA Software Package Developed by Probe Software
Lung Bioassay of Ground Dwelling Mammals from the Grand Canyon Uranium Breccia Pipe Region Using Scanning Electron Microscopy
In situ geochemical data related to the gold-quartz veins of Grass Valley, California, 2014-2015
Below are multimedia items associated with this project.
Below are publications associated with this project.
Approach for quantifying rare Earth elements at low keV
The challenges of analyzing bastnaesite (REECO3F) and hydroxylbastnaesite (REECO3OH) include beam sensitivity, quantification of light elements in a heavy element matrix, the presence of elements that cannot be analyzed with EPMA (H), and the use of x-ray lines whose physical constants are not well known. To overcome some of these challenges, Ca, La, Ce, Pr, Nd, and Sm were analyzed at 15 keV acce
Paragenesis of an orogenic gold deposit: New insights on mineralizing processes at the Grass Valley District, California
LA-ICPMS U-Pb dating reveals cassiterite inheritance in the Yazov granite, Eastern Siberia: Implications for tin mineralization
Monazite and cassiterite Usingle bondPb dating of the Abu Dabbab rare-metal granite, Egypt: Late Cryogenian metalliferous granite magmatism in the Arabian-Nubian Shield
The complexity of mudstone diagenesis - some insight from the Tøyen Formation, Lower to Middle Ordovician, southern Sweden
Apatite trace element geochemistry and cathodoluminescent textures—Acomparison between regional magmatism and the Pea Ridge IOA-REE andBoss IOCG deposits, southeastern Missouri iron metallogenic province, USA
Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes
Absence of magnetite microlites, geochemistry of magnetite veins and replacements in IOA deposits, SE Missouri, USA: Relations to intermediate intrusions
U-Pb geochronology of tin deposits associated with the Cornubian Batholith of southwest England: Direct dating of cassiterite by in situ LA-ICPMS
Method to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy
Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Geochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA
Below are news stories associated with this project.
- Overview
The USGS Denver Microbeam Laboratory provides chemical analysis and characterization of rocks, minerals, and environmental samples in support of a wide variety of USGS projects related to mineral resources, including research projects funded by the USGS Mineral Resources Program. The research applications for these projects range from mineral resource research and assessments, to geologic mapping and geochronology, to geologic hazards and radioactive waste disposal, to the environment and human health.
Additional Information
For additional information on the laboratory facilities and equipment, visit the Denver Microbeam Laboratory site.
- Science
The Denver Microbeam Laboratory has provided support to these Mineral Resources Program projects:
Filter Total Items: 27Uranium Mineral Systems
To assure adequate uranium to supply electricity from nuclear power, the US Geological Survey is working to better understand the genetic controls, distribution, and quantities of domestic uranium. Because of the heavy reliance on imported uranium, scientists also lead international groups of uranium resource experts to monitor world uranium supply. This research benefits the mining industry...Integrated Hyperspectral, Geophysical and Geochemical Studies of Yellowstone National Park Hydrothermal Systems
We are researching the subsurface groundwater flow systems in Yellowstone and the relation of these systems to understanding the regional movement of water in a volcanic center. New geophysical data will be integrated with existing data sets from hyperspectral data from Yellowstone's thermal areas and thermal water geochemistry to help define regionally extensive mineral assemblages, the evolution...Development of USGS Geochemical Reference Materials
The project focus was the development of traditional and microanalytical reference materials that support USGS geochemical investigations. Development of new microanalytical reference materials allows USGS scientists and outside customers to examine a greater range of sample types while maintaining a high degree of data reliability.Isotope and Chemical Methods for Mineral and Geoenvironmental Assessments and Support of USGS Science Strategy
This Project integrates several geochemical tools—stable isotope geochemistry, noble gas geochemistry, active gas geochemistry, single fluid inclusion chemistry, and fluid inclusion solute chemistry—in studies of the processes that form mineral deposits and the processes that disrupt them during mining or natural weathering. Research is directed toward fundamental scientific questions or, in...National Geochemical Database
The National Geochemical Database project assembles, reformats, corrects, and archives historical data obtained from the geochemical analysis of millions of geologic samples collected for USGS studies. These data, representing hundreds of millions of dollars' worth of USGS research, are provided to USGS researchers; other Federal agencies; State Geological Surveys and Environmental Protection...Non-Traditional Stable Isotopes
Understanding the genesis of ore deposits and their behavior in the environment is a subject of great importance to the Nation. A relatively new tool to aid in these efforts to investigate the origin and environmental effects of ore deposits is the use of "heavy" metal stable isotopes. Our research objectives are to utilize various isotopic systems to advance our understanding of ore genesis and...Critical Elements in Carbonatites: From Exploration Targets to Element Distribution
Critical elements are essential to the modern economy and have potential supply chain disruptions, but compared to most base and precious metals, little work has been done in understanding ore-grade enrichments. Carbonatites are the primary source of the worlds light rare earth elements and niobium, and a potential source for heavy rare earths, scandium, tantalum, and thorium. Project objectives...Argon Geochronology
This project supports the USGS argon geochronology laboratory in Denver. The USGS 40Ar/39Ar geochronology laboratory is a state-of-the-art research facility for determining absolute ages of minerals and rocks. The 40Ar/39Ar laboratory contributes critical geochronology to individual USGS research projects and to partners in academia and other Federal agencies. This laboratory develops methodology...Sediment-Hosted Copper Deposits in the Lake Superior Portion of the Midcontinent Rift System
This project is focused on the sediment-hosted copper deposits of the Midcontinent Rift, with three main objectives: 1) describe the ore mineralogy and geochemistry of the White Pine and Copperwood deposits, 2) evaluate whether hydrothermal alteration in footwall rocks can be used as a vector towards ore, and 3) provide a careful scoping study to evaluate whether unconventional platinum-group...Trace Metal Mobility in the Yellow Pine Mining District, Idaho
The study objective is to conduct an integrated, interdisciplinary study on source areas, biogeochemical transformations, and physical and biological pathways for trace metal transport in a tributary of the Snake River watershed, focusing on the Sugar Creek watershed. The historical Cinnabar mercury mine site is at the headwaters of Cinnabar Creek, a tributary to Sugar Creek. This integrated...Iron Oxide-Copper-Cobalt-Gold-Rare Earth Element Deposits of Southeast Missouri—From the Ore Deposit Scale to a Global Deposit Model
The project main objectives are to: 1) geologically, characterize the setting and origin of the iron-copper-cobalt-gold-rare earth element deposits, and advance the knowledge of rare earth element and Co potential within iron oxide-copper-gold (IOCG) deposits of southeast Missouri, and 2) geophysically delineate and characterize the subsurface Precambrian geology using existing ground and new...USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response
USGS is conducting sampling, monitoring, and modeling in the Patagonia Mountains and nearby regions in Arizona to identify contaminant risk potential of legacy and proposed mine sites and to develop classification criteria for predicting vulnerabilities and targeted sources and sinks of metal contaminants. - Data
Below are data or web applications associated with this project.
Table of Electron Probe Microanalyses of Native Copper and Sulfide Minerals from the White Pine Sediment-hosted Copper Deposit, Michigan
This data release provides electron microprobe geochemical data that was collected as part of a scoping study to evaluate whether unconventional critical element resources may be associated with sediment-hosted copper systems in the Midcontinent Rift. We report abundances of trace elements in native copper and sulfide minerals in 12 thin sections from samples of the Mesoproterozoic lower NonesuchTable of Electron Probe Microanalyses of Cassiterite from the Sullivan Pb-Zn-Ag Deposit, British Columbia
This dataset contains results from electron microprobe analyses of cassiterite from the Sullivan Pb-Zn-Ag deposit, British Columbia. These data were collected from two samples and may not reflect the overall variability present at the deposit. An ASCII text file of results is provided in comma-separated by value (csv) format. The file has the name "2019-07-09_Sullivan_Cassiterite".Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA
This data release compiles the X-ray diffraction and electron microscopy analyses of drill core samples collected by the U.S. Geological Survey that were selected to typify the uranium-copper ore bodies of the Canyon deposit. The deposit is hosted by a solution-collapse breccia pipe, in which mineralization exists from about 650 to 2,100 ft (200 to 640 m) below the surface (Mathisen and others, 20U-Pb data for inherited cassiterite in "Tin Granites", an example from the Yazov Granite, Eastern Siberia
Zircon (ZrSiO4) and cassiterite (SnO2) samples were collected by the U.S. Geological Survey (USGS) from the Yazov Granite, Transbaikalia region, Eastern Siberia, Russia. Samples (in the form of mounted loose grains) were prepared and analyzed for direct age dating on a laser ablation inductively coupled plasma mass spectrometer (LA?ICPMS) system at the USGS in Denver, Colorado from February 2017 tU-Pb data for Origin of Tin Mineralization in the Sullivan Pb-Zn-Ag Deposit, British Columbia: Constraints from Textures, Geochemistry, and LA-ICP-MS U-Pb Geochronology of Cassiterite
Cassiterite (SnO2) samples were collected throughout the underground Sullivan Mine near Kimberley, British Columbia. Samples (in the form of mounted loose grains, polished thin sections, and rock mounts) were prepared and analyzed for direct age dating on a laser ablation inductively coupled plasma mass spectrometer (LA-ICPMS) system at the U.S. Geological Survey in Denver, Colorado in February anGeochemical and mineralogical analyses of uranium ores from the Hack II and Pigeon deposits, solution-collapse breccia pipes, Grand Canyon region, Mohave and Coconino Counties, Arizona, USA
This data release compiles the whole-rock geochemistry, X-ray diffraction, and electron microscopy analyses of samples collected from the uranium ore bodies of two mined-out deposits in the Grand Canyon region of northwestern Arizona - the Hack II and Pigeon deposits. The samples are grab samples of ore collected underground at each mine by the U.S. Geological Survey (USGS) during the mid-1980s, wTables of electron probe microanalyses from the Copperwood sediment-hosted stratiform copper deposit, Michigan, USA
This data release provides electron microprobe analyses of ore minerals from the Copperwood sediment-hosted stratiform copper deposit in the Upper Peninsula of Michigan. The minerals include bornite, chalcocite, native copper, native silver, and pyrite. Minerals were analyzed for Ag, As, Co, Cu, Fe, Hg, Ni, Pb, S, Sb, and Zn. Results with acceptable totals that lie between 98.5 and 101.5% show thaU-Pb data for: Monazite and cassiterite U-Pb dating of the Abu Dabbab rare-metal granite, Egypt: Late Cryogenian metalliferous granite magmatism in the Arabian-Nubian Shield
Cassiterite (SnO2) samples were collected from alluvial ore concentrate from the Abu Dabbab Granite in eastern Egypt. Samples (in the form of mounted loose grains) were prepared and analyzed for direct age dating on a laser ablation inductively coupled plasma mass spectrometer (LA-ICPMS) system at the U.S. Geological Survey in Denver, Colorado in February 2019. This data release accompanies the puGeochemical data supporting a comparison of apatite between regional magmatism and the Pea Ridge Iron Oxide-Apatite-Rare Earth Element (IOA-REE) and Boss Iron Oxide-Copper-Cobalt-Gold-REE Deposits (IOCG) deposits, southeastern Missouri, USA
This data release presents high-spatial resolution geochemical analyses collected from Mesoproterozoic apatite crystals in igneous rocks from the St. Francois Mountains terrane and coeval ore rocks from the Pea Ridge iron oxide-apatite-rare earth element (IOA-REE) and Boss iron oxide-copper-gold (IOCG) deposits. These deposits are located in the southeast Missouri iron metallogenic province. TheseData Dictionary for Electron Microprobe Data Collected with Probe for EPMA Software Package Developed by Probe Software
This data dictionary describes most of the possible output options given in the Probe for EPMA software package developed by Probe Software. Examples of the data output options include sample identification, analytical conditions, elemental weight percents, atomic percents, detection limits, and stage coordinates. Many more options are available and the data that is output will depend upon the endLung Bioassay of Ground Dwelling Mammals from the Grand Canyon Uranium Breccia Pipe Region Using Scanning Electron Microscopy
Small mammal lung tissue sections were examined to help assess the effects of weathering on bioavailability and toxicity from sites in different phases of the mine cycle within the Grand Canyon area. Hematoxylin and eosin slides of lung tissue from brush mouse, deer mice, and pocket gophers were examined by a veterinary pathologist who marked areas of the tissue that showed normal, inflammation, bIn situ geochemical data related to the gold-quartz veins of Grass Valley, California, 2014-2015
In situ geochemical data were obtained for pyrite crystals and native gold from two distinct vein sets in the Grass Valley gold district, California. Samples of the N-S veins were collected underground at the Empire Mine State Historic Park and samples of the E-W veins were collected from drill core provided by the Idaho-Maryland Mining Corporation in 2008. These geochemical data were analyzed to - Multimedia
Below are multimedia items associated with this project.
- Publications
Below are publications associated with this project.
Filter Total Items: 52Approach for quantifying rare Earth elements at low keV
The challenges of analyzing bastnaesite (REECO3F) and hydroxylbastnaesite (REECO3OH) include beam sensitivity, quantification of light elements in a heavy element matrix, the presence of elements that cannot be analyzed with EPMA (H), and the use of x-ray lines whose physical constants are not well known. To overcome some of these challenges, Ca, La, Ce, Pr, Nd, and Sm were analyzed at 15 keV acce
AuthorsHeather A. LowersParagenesis of an orogenic gold deposit: New insights on mineralizing processes at the Grass Valley District, California
The Grass Valley orogenic gold district in the Sierra Nevada foothills province, central California, is the largest historical gold producer of the North American Cordillera. Gold mineralization is associated with shallowly dipping north-south veins hosted by the 160 Ma Grass Valley granodiorite to the southwest of the Grass Valley fault and steeply dipping east-west veins in accreted oceanic rockAuthorsRyan Taylor, Thomas Monecke, T. James Reynolds, Jochen MoneckeLA-ICPMS U-Pb dating reveals cassiterite inheritance in the Yazov granite, Eastern Siberia: Implications for tin mineralization
U-Pb dating of cassiterite and zircon from the Yazov granite (Transbaikalia region, Eastern Siberia, Russia) and cassiterite from spatially associated tin mineralization in the Tuyukan ore district in the Tonod uplift was conducted using in situ laser ablation inductively coupled plasma mass spectrometry. These analyses allow comparison of isotopic systematics for both minerals, especially relatedAuthorsLeonid A. Neymark, Christopher S. Holm-Denoma, Anatoly Larin, Richard J. Moscati, Yulia PlotkinaMonazite and cassiterite Usingle bondPb dating of the Abu Dabbab rare-metal granite, Egypt: Late Cryogenian metalliferous granite magmatism in the Arabian-Nubian Shield
The Abu Dabbab rare-metal granite in the Eastern Desert of Egypt is a highly-evolved alkali-feldspar granite with transitional magmatic-hydrothermal features. Extreme geochemical fractionation and the associated significant TaSn resource make the Abu Dabbab intrusion an important feature in the metallogenic evolution of the Arabian-Nubian Shield. UPb dating by laser ablation sector field (SF)-ICPMAuthorsBernd Lehmann, Basem Zoheir, Leonid A. Neymark, Armin Zeh, Ashraf Emam, Abdelhady Radwan, Rongqing Zhang, Richard J. MoscatiThe complexity of mudstone diagenesis - some insight from the Tøyen Formation, Lower to Middle Ordovician, southern Sweden
The Lower to Middle Ordovician Tøyen Shale in southern Sweden, a biostratigraphically well-dated siliciclastic mudstone unit, shows 18 distinct authigenic cements that include sulfides, carbonates, silicates, clays, and phosphates. Marcasite, sphalerite, galena, and six texturally distinct types of pyrite characterize the sulfides whereas only one type of dolomite and three different generations oAuthorsSven Egenhoff, Neil Fishman, Heather A. Lowers, Per AhlbergApatite trace element geochemistry and cathodoluminescent textures—Acomparison between regional magmatism and the Pea Ridge IOA-REE andBoss IOCG deposits, southeastern Missouri iron metallogenic province, USA
The southeast Missouri iron metallogenic province contains a remarkable wealth of historically important Fe, Cu, Au, and rare earth element (REE) deposits including the Pea Ridge iron oxide-apatite-rare earth element (IOA-REE) deposit and the Boss iron oxide-copper-gold (IOCG) deposit. These deposits are coeval with silicic and intermediate composition magmatism in the St. Francois Mountains terraAuthorsCelestine N. Mercer, Kathryn E. Watts, Juliane GrossGeochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes
The paragenesis, textures, and chemical compositions of secondary hematite in regional potassic altered rhyolites, four IOA deposits, the sedimentary iron deposit at Pilot Knob and the Boss IOCG deposit in SE Missouri were determined and compared to primary magnetite from the IOA and IOCG deposits. Magnetite is composed of elements characteristics of mafic to intermediate intrusions whereas hematiAuthorsCorey J. Meighan, Albert H. Hofstra, Erin E. Marsh, Heather A. Lowers, Alan KoenigAbsence of magnetite microlites, geochemistry of magnetite veins and replacements in IOA deposits, SE Missouri, USA: Relations to intermediate intrusions
The paragenesis, textures, and chemical compositions of magnetite in two mafic to intermediate intrusions and four IOA deposits in SE Missouri were studied to discriminate between igneous and hydrothermal sources. In this study, we found that replacement magnetite with mineral inclusion-rich cores yields erroneously high Ti, Al, Si, Mg, and Mn contents as determined by EMP and LA-ICP-MS due to ruAuthorsCorey J. Meighan, Albert H. Hofstra, David Adams, Erin E. Marsh, Heather A. Lowers, Alan KoenigU-Pb geochronology of tin deposits associated with the Cornubian Batholith of southwest England: Direct dating of cassiterite by in situ LA-ICPMS
The Cornwall and Devon vein- and greisen-type copper and tin deposits of southwest England are spatially and genetically related to shallow-seated granitic intrusions. These late Variscan intrusions, collectively known as the Cornubian Batholith, extend over 200 km and form a continuous granitic spine from the Isles of Scilly Granite in the west to the Dartmoor Granite in the east. The granitic plAuthorsRichard J. Moscati, Leonid A. NeymarkMethod to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy
Humans accumulate large numbers of inorganic particles in their lungs over a lifetime. Whether this causes or contributes to debilitating disease over a normal lifespan depends on the type and concentration of the particles. We developed and tested a protocol for in situ characterization of the types and distribution of inorganic particles in biopsied lung tissue from three human groups using fielAuthorsHeather A. Lowers, George N. Breit, Matthew Strand, Renee M. Pillers, Gregory P. Meeker, Todor I. Todorov, Geoffrey S. Plumlee, Ruth E. Wolf, Maura Robinson, Jane Parr, Robert J. Miller, Steve Groshong, Francis Green, Cecile RoseCharacterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Commercially produced vermiculite insulation from Libby, Montana, contains trace levels of asbestiform amphibole, which is known to cause asbestos-related diseases. When vermiculite insulation is found in a building, evaluation for its potential asbestos content traditionally involves collecting a sample from an attic or wall and submitting it for time-consuming analyses at an off-site laboratory.AuthorsGregg A. Swayze, Heather A. Lowers, William Benzel, Roger N. Clark, Rhonda L. Driscoll, Zac S. Perlman, Todd M. Hoefen, M. Darby DyarGeochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA
The Bokan Mountain igneous complex (BMIC) is a typical example of a peralkaline intrusive system that has evolved to the point of developing late stage HFSE- and REE-rich silicic pegmatites and dikes. The Dotson Zone comprises a series of felsic dikes that extend from the southeast margin of the composite pluton and may represent an important resource of critical HREEs. Petrographically, the primaAuthorsCliff D. Taylor, Heather A. Lowers, David Adams, R. James Robinson - News
Below are news stories associated with this project.