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Albert H Hofstra (Former Employee)

Science and Products

critical mineral distribution map

Systems Approach to Critical Minerals Inventory, Research, and Assessment

This project supports the Earth Mapping Resources Initiative (EarthMRI) by developing a mineral systems approach for defining focus areas. This project is investigating domestic sources of critical minerals in three sequential stages: inventory, research, and assessment. 1) Inventory the abundance of critical minerals in ore, minerals, and processed materials from major deposits in each system...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Earth Mapping Resources Initiative (Earth MRI)
Systems Approach to Critical Minerals Inventory, Research, and Assessment

Systems Approach to Critical Minerals Inventory, Research, and Assessment

This project supports the Earth Mapping Resources Initiative (EarthMRI) by developing a mineral systems approach for defining focus areas. This project is investigating domestic sources of critical minerals in three sequential stages: inventory, research, and assessment. 1) Inventory the abundance of critical minerals in ore, minerals, and processed materials from major deposits in each system...
Learn More
Li brine and clay conceptual model

Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

The purpose of this project is to trace the lithium (Li) geochemical cycle in the Great Basin, with an emphasis on the pathways that lead to the development of lithium clay and brine resources.
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

The purpose of this project is to trace the lithium (Li) geochemical cycle in the Great Basin, with an emphasis on the pathways that lead to the development of lithium clay and brine resources.
Learn More

National Geochemical Database on Ore Deposits: New data featuring fusion digestion analytical methods National Geochemical Database on Ore Deposits: New data featuring fusion digestion analytical methods

There is a growing demand for commodities (elements, compounds, minerals) used in today's advanced technologies. Critical minerals are usually found in ore deposits that are deemed vital to economic and national security. National Geochemical Database on Ore Deposits: New data featuring fusion digestion (NGDOD) analytical methods contains chemistry and geologic information for 16,579 ore...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Noble Gas Isotopic Data from Fluid Inclusions Contained in the Te-bearing Adularia-Sericite Epithermal Au-Ag Deposits in a Calc-Alkaline Magmatic Arc, NE China Noble Gas Isotopic Data from Fluid Inclusions Contained in the Te-bearing Adularia-Sericite Epithermal Au-Ag Deposits in a Calc-Alkaline Magmatic Arc, NE China

The contents of this data release represent the results of the noble gas composition analysis and are presented in support of the planned publication Gao et al., 2023, titled Lead and noble gas isotopic constraints on the origin of Te-bearing adularia-sericite epithermal Au-Ag deposits in a calc-alkaline magmatic arc. Tellurium (Te)-bearing adularia-sericite epithermal Au-Ag deposits are...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district

This dataset is a collection of geochemical data on samples from the Stibnite-Yellow Pine district of Idaho. The datasets include: whole rock geochemistry; lead, strontium and neodymium isotope chemistry of sulfides and whole rock samples by isotope dilution-thermal-mass spectrometry (ID-TIMS); in situ sulfur isotope chemistry of sulfides by laser ablation-multi collector-inductively...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

National Geochemical Database on Ore Deposits: Legacy data National Geochemical Database on Ore Deposits: Legacy data

There is a growing demand for commodities (elements, compounds, minerals) used in today's advanced technologies. Critical minerals are usually found in ore deposits that are deemed vital to economic and national security. The National Geochemical Database on Ore Deposits: Legacy data (NGDOD) contains chemistry and geologic information for nearly 30,000 historic ore and ore-related rock...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Melt inclusion and mineral geochemical analyses supporting the evaluation of petrogenesis, degassing, and metallogenic potential of mid-Cenozoic rhyolite magmas in northern Nevada, USA (ver. 2.0, March 2025) Melt inclusion and mineral geochemical analyses supporting the evaluation of petrogenesis, degassing, and metallogenic potential of mid-Cenozoic rhyolite magmas in northern Nevada, USA (ver. 2.0, March 2025)

This data release presents geochemical analyses of silicate melt inclusions, host quartz phenocrysts, and biotite phenocrysts in samples collected by the U.S. Geological Survey (USGS) from mid-Cenozoic rhyolitic rocks from northern Nevada. Igneous intrusions and volcanic rocks in this study encompass nineteen rhyolitic samples from five magmatic centers across northeastern Nevada...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Global Geochemical Database for Critical Minerals in Archived Mine Samples Global Geochemical Database for Critical Minerals in Archived Mine Samples

The Critical Minerals in Archived Mine Samples Database (CMDB) contains chemistry and geologic information for historic ore and ore-related rock samples from mineral deposits in the United States. In addition, the database contains samples from archetypal deposits from 27 other countries in North America, South America, Asia, Africa and Europe. Samples were obtained from archived ore...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Improved Automated Identification and Mapping of Iron Sulfate Minerals, Other Mineral Groups, and Vegetation using Landsat 8 Operational Land Imager Data, San Juan Mountains, Colorado, and Four Corners Region Improved Automated Identification and Mapping of Iron Sulfate Minerals, Other Mineral Groups, and Vegetation using Landsat 8 Operational Land Imager Data, San Juan Mountains, Colorado, and Four Corners Region

Multispectral remote sensing data acquired by the Landsat 8 Operational Land Imager (OLI) sensor were analyzed using a new, automated technique to generate a map of exposed mineral and vegetation groups in the western San Juan Mountains, Colo., and the Four Corners Region of the United States. Band ratio results were combined into displayed mineral and vegetation groups using Boolean...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center
Filter Total Items: 82

Pre-eruptive characteristics of “suspect” silicic magmas in Carlin-type Au-forming systems Pre-eruptive characteristics of “suspect” silicic magmas in Carlin-type Au-forming systems

World-class Carlin-type Au deposits hosted in sedimentary rock were formed when profuse Eocene silicic magmatism swept across northern Nevada in response to arc migration. Carlin-type Au deposits formed along with porphyry/skarn Cu-Mo-W-Au deposits, epithermal Ag-Au deposits, and distal disseminated Ag-Au deposits. But unlike these other Au-bearing deposits that have clear associations...
Authors
Celestine N. Mercer, Julie Roberge, Regina Marie Khoury, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Geochemistry and thermometry of magnetite veins and replacements in iron ore deposits from the Iron Springs district, SW Utah, USA: Relation to magmatic and hydrothermal processes Geochemistry and thermometry of magnetite veins and replacements in iron ore deposits from the Iron Springs district, SW Utah, USA: Relation to magmatic and hydrothermal processes

Ore-genesis, texture, chemical compositions, and thermometry of magnetite were used to better evaluate the origins of iron ore deposits across the Iron Spring district, Utah. Trace element compositions, determined by LA-ICP-MS, were used to calculate temperatures based on XMg numbers and characterize the trace element signatures of magmatic and hydrothermal magnetite. Magnetite occurs as...
Authors
Corey J. Meighan, Ryan D. Taylor, Albert H. Hofstra, Jay Michael Thompson
By
Geology, Geophysics, and Geochemistry Science Center

Critical mineral inventory of select IOA-IOCG deposits, southwestern USA Critical mineral inventory of select IOA-IOCG deposits, southwestern USA

Critical minerals are necessary for modern technology and strategic purposes. Their increasing importance requires finding new and nontraditional resources. Samples of ore, altered, and unaltered host rock were collected from 26 iron mines and prospects in California, Nevada, and Utah to assess the potential of these deposits to host economic quantities of different critical minerals...
Authors
Ryan D. Taylor, Corey J. Meighan, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Critical minerals in orogenic (gold) and Coeur d’Alene-type mineral systems of the United States Critical minerals in orogenic (gold) and Coeur d’Alene-type mineral systems of the United States

Orogenic and Coeur d’Alene-type mineral systems are produced by metamorphic devolatilization of thick volcanic or siliciclastic sedimentary rock sequences and the focused flow of hydrothermal fluids upwards along crustal-scale faults. Most orogenic systems are found along the Cordilleran orogen, stretching from California northwards into Alaska, whereas most Coeur d’Alene-type systems...
Authors
Ryan D. Taylor, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Metal fingerprints of Eocene rhyolite magmas coincident with Carlin-type gold deposition in Nevada USA Metal fingerprints of Eocene rhyolite magmas coincident with Carlin-type gold deposition in Nevada USA

Eocene magmatic systems contemporaneous with world-class Carlin-type Au deposits in Nevada (USA) have been proposed by some researchers as a key ingredient for Au mineralization, though evidence conclusively demonstrating their genetic relationship remains tenuous. This study provides the first direct evidence of the pre-eruptive metal budget of volatile- and metal-charged silicic magmas
Authors
Celestine N. Mercer, Hannah R. Babel, Cameron Mark Mercer, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Critical Minerals in Ores (CMiO) database Critical Minerals in Ores (CMiO) database

Critical minerals are commodities essential to modern industrial and strategic technologies and are highly vulnerable to supply chain disruption. The Critical Minerals Mapping Initiative (CMMI) is a collaboration among the U.S. Geological Survey (USGS), the Geological Survey of Canada, and Geoscience Australia that aims to deepen global understanding of where critical minerals are...
Authors
George N.D. Case, Garth E. Graham, Christopher Lawley, Evgeniy Bastrakov, David Huston, Albert H. Hofstra, Vladimir Lisitsin, Steph Hawkins, Bronwen Wang
By
Ecosystems Mission Area, Geology, Energy, and Minerals Mission Area, Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

Science and Products

critical mineral distribution map

Systems Approach to Critical Minerals Inventory, Research, and Assessment

This project supports the Earth Mapping Resources Initiative (EarthMRI) by developing a mineral systems approach for defining focus areas. This project is investigating domestic sources of critical minerals in three sequential stages: inventory, research, and assessment. 1) Inventory the abundance of critical minerals in ore, minerals, and processed materials from major deposits in each system...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Earth Mapping Resources Initiative (Earth MRI)
Systems Approach to Critical Minerals Inventory, Research, and Assessment

Systems Approach to Critical Minerals Inventory, Research, and Assessment

This project supports the Earth Mapping Resources Initiative (EarthMRI) by developing a mineral systems approach for defining focus areas. This project is investigating domestic sources of critical minerals in three sequential stages: inventory, research, and assessment. 1) Inventory the abundance of critical minerals in ore, minerals, and processed materials from major deposits in each system...
Learn More
Li brine and clay conceptual model

Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

The purpose of this project is to trace the lithium (Li) geochemical cycle in the Great Basin, with an emphasis on the pathways that lead to the development of lithium clay and brine resources.
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

Lithium from Source to Sink: Genesis and Evolution of Li Brines and Clays

The purpose of this project is to trace the lithium (Li) geochemical cycle in the Great Basin, with an emphasis on the pathways that lead to the development of lithium clay and brine resources.
Learn More

National Geochemical Database on Ore Deposits: New data featuring fusion digestion analytical methods National Geochemical Database on Ore Deposits: New data featuring fusion digestion analytical methods

There is a growing demand for commodities (elements, compounds, minerals) used in today's advanced technologies. Critical minerals are usually found in ore deposits that are deemed vital to economic and national security. National Geochemical Database on Ore Deposits: New data featuring fusion digestion (NGDOD) analytical methods contains chemistry and geologic information for 16,579 ore...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Noble Gas Isotopic Data from Fluid Inclusions Contained in the Te-bearing Adularia-Sericite Epithermal Au-Ag Deposits in a Calc-Alkaline Magmatic Arc, NE China Noble Gas Isotopic Data from Fluid Inclusions Contained in the Te-bearing Adularia-Sericite Epithermal Au-Ag Deposits in a Calc-Alkaline Magmatic Arc, NE China

The contents of this data release represent the results of the noble gas composition analysis and are presented in support of the planned publication Gao et al., 2023, titled Lead and noble gas isotopic constraints on the origin of Te-bearing adularia-sericite epithermal Au-Ag deposits in a calc-alkaline magmatic arc. Tellurium (Te)-bearing adularia-sericite epithermal Au-Ag deposits are...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district

This dataset is a collection of geochemical data on samples from the Stibnite-Yellow Pine district of Idaho. The datasets include: whole rock geochemistry; lead, strontium and neodymium isotope chemistry of sulfides and whole rock samples by isotope dilution-thermal-mass spectrometry (ID-TIMS); in situ sulfur isotope chemistry of sulfides by laser ablation-multi collector-inductively...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

National Geochemical Database on Ore Deposits: Legacy data National Geochemical Database on Ore Deposits: Legacy data

There is a growing demand for commodities (elements, compounds, minerals) used in today's advanced technologies. Critical minerals are usually found in ore deposits that are deemed vital to economic and national security. The National Geochemical Database on Ore Deposits: Legacy data (NGDOD) contains chemistry and geologic information for nearly 30,000 historic ore and ore-related rock...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Melt inclusion and mineral geochemical analyses supporting the evaluation of petrogenesis, degassing, and metallogenic potential of mid-Cenozoic rhyolite magmas in northern Nevada, USA (ver. 2.0, March 2025) Melt inclusion and mineral geochemical analyses supporting the evaluation of petrogenesis, degassing, and metallogenic potential of mid-Cenozoic rhyolite magmas in northern Nevada, USA (ver. 2.0, March 2025)

This data release presents geochemical analyses of silicate melt inclusions, host quartz phenocrysts, and biotite phenocrysts in samples collected by the U.S. Geological Survey (USGS) from mid-Cenozoic rhyolitic rocks from northern Nevada. Igneous intrusions and volcanic rocks in this study encompass nineteen rhyolitic samples from five magmatic centers across northeastern Nevada...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Global Geochemical Database for Critical Minerals in Archived Mine Samples Global Geochemical Database for Critical Minerals in Archived Mine Samples

The Critical Minerals in Archived Mine Samples Database (CMDB) contains chemistry and geologic information for historic ore and ore-related rock samples from mineral deposits in the United States. In addition, the database contains samples from archetypal deposits from 27 other countries in North America, South America, Asia, Africa and Europe. Samples were obtained from archived ore...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Improved Automated Identification and Mapping of Iron Sulfate Minerals, Other Mineral Groups, and Vegetation using Landsat 8 Operational Land Imager Data, San Juan Mountains, Colorado, and Four Corners Region Improved Automated Identification and Mapping of Iron Sulfate Minerals, Other Mineral Groups, and Vegetation using Landsat 8 Operational Land Imager Data, San Juan Mountains, Colorado, and Four Corners Region

Multispectral remote sensing data acquired by the Landsat 8 Operational Land Imager (OLI) sensor were analyzed using a new, automated technique to generate a map of exposed mineral and vegetation groups in the western San Juan Mountains, Colo., and the Four Corners Region of the United States. Band ratio results were combined into displayed mineral and vegetation groups using Boolean...
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center
Filter Total Items: 82

Pre-eruptive characteristics of “suspect” silicic magmas in Carlin-type Au-forming systems Pre-eruptive characteristics of “suspect” silicic magmas in Carlin-type Au-forming systems

World-class Carlin-type Au deposits hosted in sedimentary rock were formed when profuse Eocene silicic magmatism swept across northern Nevada in response to arc migration. Carlin-type Au deposits formed along with porphyry/skarn Cu-Mo-W-Au deposits, epithermal Ag-Au deposits, and distal disseminated Ag-Au deposits. But unlike these other Au-bearing deposits that have clear associations...
Authors
Celestine N. Mercer, Julie Roberge, Regina Marie Khoury, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Geochemistry and thermometry of magnetite veins and replacements in iron ore deposits from the Iron Springs district, SW Utah, USA: Relation to magmatic and hydrothermal processes Geochemistry and thermometry of magnetite veins and replacements in iron ore deposits from the Iron Springs district, SW Utah, USA: Relation to magmatic and hydrothermal processes

Ore-genesis, texture, chemical compositions, and thermometry of magnetite were used to better evaluate the origins of iron ore deposits across the Iron Spring district, Utah. Trace element compositions, determined by LA-ICP-MS, were used to calculate temperatures based on XMg numbers and characterize the trace element signatures of magmatic and hydrothermal magnetite. Magnetite occurs as...
Authors
Corey J. Meighan, Ryan D. Taylor, Albert H. Hofstra, Jay Michael Thompson
By
Geology, Geophysics, and Geochemistry Science Center

Critical mineral inventory of select IOA-IOCG deposits, southwestern USA Critical mineral inventory of select IOA-IOCG deposits, southwestern USA

Critical minerals are necessary for modern technology and strategic purposes. Their increasing importance requires finding new and nontraditional resources. Samples of ore, altered, and unaltered host rock were collected from 26 iron mines and prospects in California, Nevada, and Utah to assess the potential of these deposits to host economic quantities of different critical minerals...
Authors
Ryan D. Taylor, Corey J. Meighan, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Critical minerals in orogenic (gold) and Coeur d’Alene-type mineral systems of the United States Critical minerals in orogenic (gold) and Coeur d’Alene-type mineral systems of the United States

Orogenic and Coeur d’Alene-type mineral systems are produced by metamorphic devolatilization of thick volcanic or siliciclastic sedimentary rock sequences and the focused flow of hydrothermal fluids upwards along crustal-scale faults. Most orogenic systems are found along the Cordilleran orogen, stretching from California northwards into Alaska, whereas most Coeur d’Alene-type systems...
Authors
Ryan D. Taylor, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Metal fingerprints of Eocene rhyolite magmas coincident with Carlin-type gold deposition in Nevada USA Metal fingerprints of Eocene rhyolite magmas coincident with Carlin-type gold deposition in Nevada USA

Eocene magmatic systems contemporaneous with world-class Carlin-type Au deposits in Nevada (USA) have been proposed by some researchers as a key ingredient for Au mineralization, though evidence conclusively demonstrating their genetic relationship remains tenuous. This study provides the first direct evidence of the pre-eruptive metal budget of volatile- and metal-charged silicic magmas
Authors
Celestine N. Mercer, Hannah R. Babel, Cameron Mark Mercer, Albert H. Hofstra
By
Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Critical Minerals in Ores (CMiO) database Critical Minerals in Ores (CMiO) database

Critical minerals are commodities essential to modern industrial and strategic technologies and are highly vulnerable to supply chain disruption. The Critical Minerals Mapping Initiative (CMMI) is a collaboration among the U.S. Geological Survey (USGS), the Geological Survey of Canada, and Geoscience Australia that aims to deepen global understanding of where critical minerals are...
Authors
George N.D. Case, Garth E. Graham, Christopher Lawley, Evgeniy Bastrakov, David Huston, Albert H. Hofstra, Vladimir Lisitsin, Steph Hawkins, Bronwen Wang
By
Ecosystems Mission Area, Geology, Energy, and Minerals Mission Area, Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center
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