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Minerals & deposits

Find USGS publications on mineral resources and deposits. Search commodities and geographic names, then check source reports for geology and assessment methods.

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USGS1999

Land and federal mineral ownership coverage for northwestern Colorado

This Arc/Info coverage contains land status and Federal mineral ownership for approximately 26,800 square miles in northwestern Colorado. The polygon coverage (which is also provided here as a shapefile) contains two attributes of ownership information for each polygon. One attribute indicates where the surface is State owned, privately owned, or, if Federally owned, which Federal agency manages the land surface. The other attribute indicates which minerals, if any, are owned by the Federal govenment. This coverage is based on land status and Federal mineral ownership data compiled by the U.S. Geological Survey (USGS) and three Colorado State Bureau of Land Management (BLM) former district offices at a scale of 1:24,000. This coverage was compiled primarily to serve the USGS National Oil and Gas Resource Assessment Project in the Uinta-Piceance Basin Province and the USGS National Coal Resource Assessment Project in the Colorado Plateau.

Open-File Report↗

USGS1999

Land and federal mineral ownership coverage for southern Wyoming

This Arc/Info coverage contains land status and Federal mineral ownership for approximately 37,800 square miles in southern Wyoming. The polygon coverage (which is also provided here as a shapefile) contains two attributes of ownership information for each polygon. One attribute indicates where the surface is State owned, privately owned, or, if Federally owned, which Federal agency manages the land surface. The other attribute indicates which minerals, if any, are owned by the Federal govenment. This coverage is based on land status and Federal mineral ownership data compiled by the U.S. Geological Survey (USGS) and the Wyoming State Bureau of Land Management (BLM) at a scale of 1:24,000. This coverage was compiled primarily to serve the USGS National Oil and Gas Resource Assessment and National Coal Resource Assessment Projects in the Northern Rocky Mountains/Great Plains Region.

Wyoming↗

USGS1999

Geochemical data for stream-sediment, heavy-mineral-concentrate, and rock samples collected from the Fortyseven Creek gold-arsenic-antimony-tungsten prospect, southwestern Alaska

In the summer of 1991, we conducted a reconnaissance geochemical survey around the Fortyseven Creek Au-As-Sb-W prospect that is located in the southwestern part of the Sleetmute quadrangle. At that time, this project was a small part of a more comprehensive Alaska Mineral Resource Assessment Program (AMRAP) study of the Sleemute quadrangle. AMRAP studies were conducted by the U.S. Geological Survey (USGS) to fulfill requirements of the Alaska National Interests Lands Conservation Act (Public Law 96-487, 1980) to survey certain federal lands to determine their mineral potential. Although AMRAP is no longer in operation, this study represents a small topical study that was conducted during the Sleetmute quadrangle AMRAP study. The objective of the Fortyseven Creek work was to characterize the geochemistry of samples collected downstream from the Fortyseven Creek prospect, as well as mineralized and altered rock samples collected from the prospect. In this report, we describe the samples collected in 1991, the methods used for the analysis of the samples, and the geochemical data for these samples. The data in this report are also available in digital form on computer diskette in Gray and others (1999). An interpretation of these data appears in Gray and others (1998).

Alaska↗

USGS2014

A geologic and mineral exploration spatial database for the Stillwater Complex, Montana

The Stillwater Complex is a Neoarchean, ultramafic to mafic layered intrusion exposed in the Beartooth Mountains in south-central Montana. This igneous intrusion contains magmatic mineralization that is variably enriched in strategic and critical commodities such as chromium, nickel, and the platinum-group elements. One deposit, the J-M Reef, is the sole source of primary production and reserves for platinum-group elements in the United States. A large amount of information has been collected on the Stillwater Complex. In the 1930s, academics, the U.S. Geological Survey, and the [U.S.] Bureau of Mines initiated geologic investigations on the Stillwater Complex. Since that time, more than 600 publications on the Stillwater Complex have appeared in the scientific literature. Exploration and mining companies have collected even more information since the 1920s. This report provides essential spatially referenced datasets based on geologic mapping and mineral exploration activities conducted from the 1920s to the 1990s. This information will facilitate research on the complex and provide background material needed to explore for mineral resources and to develop sound land-management policy.

Montana↗

USGS2019

Effect of size-biased sampling on resource predictions from the three-part method for quantitative mineral resource assessment—A case study of the gold mines in the Timmins-Kirkland Lake area of the Abitibi greenstone belt, Canada:

The three-part method for quantitative mineral resource assessment is used by the U.S. Geological Survey to predict, within a specified assessment area, the number of undiscovered mineral deposits and the quantity of mineral resources in those undiscovered deposits. The effects of size-biased sampling on such predictions are evaluated in a case study that involves gold mines from the Timmins-Kirkland Lake area of the Abitibi greenstone belt, Canada. The gold mines are divided, based upon the time of the assessment, into two groups: existing mines and future mines. The total produced gold for the existing mines are used to predict, with the three-part method, the total produced gold for the future mines. Then the predictions are compared to the known, total produced gold for the future mines. For comparisons using the mean, the predictions are 1.6 to 12 times too high, depending upon the time of the assessment and the probability density function characterizing the total produced gold in the existing mines. For comparisons using the median, the predictions are 1.3 to 10 times too high, depending upon the time of the assessment. The reason for these excessively high predictions is that the three-part method is based on the assumption that the total produced gold from the existing mines is representative of the total produced gold in the future mines; this assumption is inappropriate because of size-biased sampling. There is reason to be concerned that size-biased sampling adversely affected the resource predictions of previous U.S. Geological Survey assessments that were conducted with the three-part method.

Ontario Province, Quebec Province↗

USGS2025

World minerals outlook—Cobalt, gallium, helium, lithium, magnesium, palladium, platinum, and titanium through 2029

Given the rapid expansion in the demand for mineral commodities that underpin worldwide economic growth and technological advancement, information regarding expected country-level mine production and production capacity is becoming increasingly important to industry stakeholders, end users, and policymakers. Production capacity can limit future supply, depending on how rapidly that capacity is able to expand. Current capacity can be evaluated on the basis of past production. Decreases to future capacity can be taken into account from announcements of planned shutdowns of mines or processing facilities, which are frequently publicized well in advance of such closures. Likewise, capacity expansions, which usually involve multiple stages—such as permitting, financing, and construction (all of which take time)—can also be estimated. As such, it is possible to evaluate midterm future capacity based on estimates of today’s capacities along with consideration of future investment plans. This World Minerals Outlook provides estimated capacities for cobalt, gallium, helium, lithium, magnesium, palladium, platinum, and titanium for 2025 through 2029. The results of this analysis indicate that two mineral commodities important to the manufacture of lithium-ion batteries—cobalt and lithium—are expected to have large capacity growth in the next few years, likely owing to expectations for increased demand for these batteries. For gallium, helium, palladium, and platinum, capacity is expected to remain stable or exhibit moderate growth. Still, these expected capacity levels are higher than current production, allowing for future production growth. The production capacity outlook is opaque for magnesium and titanium metal, which have a significant fraction of current production in nonmarket economies, such as China and Russia. Ultimately, though, where free market conditions prevail, full utilization of capacity potential for those commodities is likely to depend on supply deficits and prices that are above production costs.

Scientific Investigations Report↗

USGS1988

Water resources of Miner County, South Dakota

Miner County is a rural agricultural area of 572 sq mi in east-central South Dakota. All streams in the county are intermittent and usually are recharged only from spring snowmelt and precipitation. Most ponds and sloughs may go dry in summer and during drought conditions, while larger lakes and ponds will contain water year round. Three major confined glacial aquifers underlie Miner County. The Floyd aquifer, buried beneath 25-150 ft of glacial drift, ranges from 10-100 ft in thickness. Water levels in the Floyd range from flowing to 56 ft below land surface. Properly constructed wells in the aquifer may produce as much as 1,200 gal/min. The Floyd aquifer offers the greatest potential for irrigation or other large yield development. Predominant chemical constituents in water from the Floyd aquifer are sodium, calcium and sulfate; however, there is a wide variation in the chemical composition of the water. For the most part it is suitable for irrigation. The Howard aquifer, is buried beneath 80-350 ft of glacial drift and ranges from 4-170 ft in thickness. Water levels in the Howard aquifer range from 16-200 ft below land surface. The Ramona aquifer underlies about 70 sq mi and is buried beneath 25-170 ft of glacial drift and ranges from 4-32 ft in thickness. Water levels in the Ramona range from 10-105 ft below land surface. Four bedrock aquifers underlie Miner County. The uppermost aquifer is the Niobrara Formation, buried by 60-600 ft of Pierre Shale and/or glacial drift with a thickness ranging from 10-120 ft. Water levels in the aquifer range from 6 ft above land surface to 200 ft below land surface. The Codell Sandstone Member of the Carlile Shale which underlies the Niobrara Formation is at depths ranging from 120-720 ft below land surface. It ranges from 10-120 ft in thickness. Water levels in the Codell aquifer range from flowing at land surface to 235 ft below land surface. Water from the aquifer generally is not suitable for irrigation. The Dakota Formation is buried by 400-1,000 ft of bedrock and glacial drift and is separated from the Codell aquifer by overlying carbonate rock and shale. The Dakota aquifer ranges from 10-400 ft in thickness. Water levels in the aquifer range from 25 ft above land surface to 260 ft below land surface. Water from the aquifer generally is not suitable for irrigation. (Lantz-PTT)

Water-Resources Investigations Report↗

USGS2023

Beyond conductive targets: Characterizing lithium-prospective lacustrine evaporite mineral systems of North America’s Basin and Range Province with regional-scale AEM

The Basin and Range province of North America hosts substantial lacustrine evaporite mineral systems prospective for lithium, a critical mineral currently listed for mineral resource assessment by the U.S. Geological Survey. Airborne electromagnetic (AEM) surveys are being conducted to support these assessments by identifying shallow clays and brines, as well as through improving the shallow subsurface geologic framework of the regional fluid flow system. In 2022-2023, three focus areas with proven lithium resources or considered highly prospective for lithium are being surveyed. Results from this effort can help to improve our understanding of the geologic conditions and geophysical signatures associated with known resource regions and benefit future lithium resource assessments by identifying regions with similar geophysical and geologic characteristics.

Arizona, California, Idaho, Nevada, Oregon, Utah↗

USGS1981

Physical factors that could restrict mineral supply

Stages in the metal supply process are affected by each of the following physical (geologic) factors: (1) geographic distribution of concentrations of potential ore minerals, (2) depth of these concentrations, (3) mineralogy, (4) grain size of the minerals, and (5) grade and (6) tonnages of the concentrations. For mineral deposits of each type in each geologic and political environment, the lowest cost metal will tend to be produced first because: (1) the largest deposits tend to be found first, (2) the few largest deposits should reap the benefits of economies of scale and will tend to account for the lion’s share of total metal, (3) higher grade deposits that require substantially less energy per ton of metal than do lower grade deposits will be mined first, and (4) deposits that have the mineralogy and grain sizes that are relatively cheap to process will be produced first. Shallow deposits that are relatively cheap to find and mine and deposits near existing infrastructure will also be produced first. Because stages in the supply process are sequential, problems at any stage caused by the physical factors are reflected in subsequent stages and adversely affect production costs. In the long term, effects of such problems will be not physical shortages of metals but a rapid or persistent increase in real prices of metals.

Economic Geology↗

USGS1951

Fluorometric determination of zirconium in minerals

The increasing use of zirconium in alloys and in the ceramics industry has created renewed interest in methods for its determination. It is a common constituent of many minerals, but is usually present in very small amounts. Published methods tend to be tedious, time-consuming, and uncertain as to accuracy. A new fluorometric procedure, which overcomes these objections to a large extent, is based on the blue fluorescence given by zirconium and flavonol in sulfuric acid solution. Hafnium is the only element that interferes. The sample is fused with borax glass and sodium carbonate and extracted with water. The residue is dissolved in sulfuric acid, made alkaline with sodium hydroxide to separate aluminum, and filtered. The precipitate is dissolved in sulfuric acid and electrolysed in a Melaven cell to remove iron. Flavonol is then added and the fluorescence intensity is measured with a photo-fluorometer. Analysis of seven standard mineral samples shows excellent results. The method is especially useful for minerals containing less than 0.25% zirconium oxide.

Analytical Chemistry↗

USGS1984

LASER MICROPROBE 40Ar/39Ar DATING OF MINERAL GRAINS IN SITU.

A laser-microprobe attached to a mass spectrometer for **4**0Ar/**3**9Ar age determination of single mineral grains in geological materials has been made operational at the US Geological Survey, Reston, VA. This microanalytical technique involves focusing a pulsed laser beam onto a sample contained in an ultra-high vacuum chamber attached to a rare-gas mass spectrometer. Argon in the neutron-irradiated sample is released by heating with the laser pulse and its isotopic composition is measured to yield an **4**0Ar/**3**9Ar age. Laser probe **4**0Ar/**3**9Ar ages of single mineral grains measured in situ can aid greatly in understanding the chronology of many geological situations where datable minerals are present but are not physically separable in quantities needed for conventional age dating.

Scanning Electron Microscopy↗

USGS1985

DISTRIBUTION OF TRACE ELEMENTS IN COAL MINERALS OF SELECTED EASTERN UNITED STATES COALS.

The association of 34 elements with minerals found in coal was determined by a combination of analytical techniques on size and density fractions of low-temperature ash (LTA). Instrumental neutron activation analysis was used to determine the concentrations of the elements, and X-ray diffraction analysis, scanning electron microscopy, and scanning transmission electron microscopy were used to identify the minerals present in the LTA. The distribution of elemental and mineral concentrations in different size fractions was also determined. Between 35 and 60 weight percent of the LTA was composed of particles smaller than 2 mu m.

Conference Paper↗

USGS1985

MARINE MINERAL RESOURCES - AN UPDATE AND INTRODUCTION.

This article briefly traces the status of marine minerals development, and it describes papers presented in this special issue on the subject. Subjects covered include types of deposits, marine mining in Canada, Manganese nodules, metalliferous sulfides as seabed minerals, metallurgical processes for reducing sulfide minerals, U. S. phosphate industry, construction materials and placers, and industry problems.

Marine Technology Society Journal↗

USGS1984

U. S. GEOLOGICAL SURVEY MARINE-MINERALS RESEARCH.

Summary form only given. The US Exclusive Economic Zone is an area approximately one and two-thirds the size of the land area of the United States. In this frontier area, US Geological Survey (USGS) research in marine minerals is aimed at three objectives: (1) defining geologic settings of potential mineral resources; (2) understanding the processes by which seafloor nonliving resources form; and (3) estimating the resource potential. Potential resources of primary interest are cobalt-rich manganese seafloor crusts, polymetallic sulfides in hydrothermal vent areas on the seafloor, and heavy-mineral placer deposits. Research activities include studies of manganese-crust samples from oceanographic-institution archives and a USGS research cruise through the central and southern Pacific. Preliminary results confirm that cobalt is concentrated by as much as 2. 5% in the manganese crusts at water depths of 1000-2600 m; further research on the precipitation processes and patterns of crust formation will be needed to understand the origin, occurrence patterns, and resource potential of these crusts. Research cruises have revealed a zone of polymetallic sulfide vent deposits a few hundred meters long in the Juan de Fuca spreading center.

Conference Paper↗

USGS1984

Mineral resources of the Atlantic Exclusive Economic Zone

Potential mineral resources of the Atlantic Exclusive Economic Zone (including the Gulf of Mexico and US Caribbean areas) include petroleum, sand and gravel, phosphorite, placer deposits of heavy mineral sands, ferromanganese nodules, and fresh water. Although major efforts have been made to search for petroleum, the oil and gas resources of the region are well known only in the western Gulf Shelf and more exploration is under way. Heavy-mineral placer deposits, which may be sources of titanium, gold, rare earths, etc. , have been sampled, but the extent and, therefore, economic value of the deposits have not been identified. Sand and gravel, phosphorite, and ferromanganese nodules all are represented by fairly well established deposits, and only modified market conditions would be necessary to cause detailed exploration and mining.

Conference Paper↗

USGS1987

LEAD, TIN, AND PRECIOUS-METAL MINERALIZATION IN THE U. S. VIRGIN ISLANDS.

This regional geochemical study of the U. S. Virgin Islands demonstrates the presence of a widespread base-metal (primarily Pb, Sn, Cu) and precious-metal (primarily Ag) mineralization on all three of the islands. The overall association: Au, Ag, Te, Sn, Pb, Cu, Zn, Sb, Bi, Mo, As and Ba shows a great similarity to that of the Bolivian silver-tin district. The single divergence from the Bolivian association is tungsten, which is totally lacking in the U. S. Virgin Islands. The delineated geochemical patterns transect all exposed rock types on the islands, including the Kingshill Marl of late Miocene age, on St. Croix. Some relationship between the geochemical patterns and the major mapped faults can be seen - especially on St. Croix. K-Ar age dating of rocks from St. Thomas and St. John indicates that they are of Tertiary rather than Cretaceous age. This and the apparent contemporaneity of the mineralization with the St. Croix graben infilling indicate a very late Miocene age for the mineralization.

Conference Paper↗

USGS1990

Enzyme leaching of surficial geochemical samples for detecting hydromorphic trace-element anomalies associated with precious-metal mineralized bedrock buried beneath glacial overburden in northern Minnesota

One objective of the International Falls and Roseau, Minnesota, CUSMAP projects was to develop a means of conducting regional-scale geochemical surveys in areas where bedrock is buried beneath complex glacially derived overburden. Partial analysis of B-horizon soils offered hope for detecting subtle hydromorphic trace-element dispersion patterns. An enzyme-based partial leach selectively removes metals from oxide coatings on the surfaces of soil materials without attacking their matrix. Most trace-element concentrations in the resulting solutions are in the part-per-trillion to low part-per-billion range, necessitating determinations by inductively coupled plasma/mass spectrometry. The resulting data show greater contrasts for many trace elements than with other techniques tested. Spatially, many trace metal anomalies are locally discontinuous, but anomalous trends within larger areas are apparent. In many instances, the source for an anomaly seems to be either basal till or bedrock. Ground water flow is probably the most important mechanism for transporting metals toward the surface, although ionic diffusion, electrochemical gradients, and capillary action may play a role in anomaly dispersal. Sample sites near the Rainy Lake-Seine River fault zone, a regional shear zone, often have anomalous concentrations of a variety of metals, commonly including Zn and/or one or more metals which substitute for Zn in sphalerite (Cd, Ge, Ga, and Sn). Shifts in background concentrations of Bi, Sb, and As show a trend across the area indicating a possible regional zoning of lode-Au mineralization. Soil anomalies of Ag, Co, and Tl parallel basement structures, suggesting areas that may have potential for Cobalt/Thunder Baytype silver viens. An area around Baudette, Minnesota, which is underlain by quartz-chlorite-carbonate-altered shear zones, is anomalous in Ag, As, Bi, Co, Mo, Te, Tl, and W. Anomalies of Ag, As, Bi, Te, and W tend to follow the fault zones, suggesting potential for lode-Au deposits. Soil anomalies of Co, Mo, and Tl appear to follow northwest-striking structures that cross the shear zones, suggesting that Thunder Bay-type mineralization may have overprinted earlier mineralization along the shear zones.

Conference Paper↗

USGS1994

McCrillisite, NaCs(Be,Li)Zr2(PO4)4.1-2H2O, a new mineral species from Mount Mica, Oxford County, Maine, and new data for gainesite

McCrillisite, a member of the gainesite group, occurs in the Mount Mica granitic pegmatite, South Paris, Oxford County, Maine. The mineral is a product of late-stage hydrothermal alteration and is associated with approximately 20 other silicate, oxide, carbonate, arsenite and phosphate minerals. Crystals occur in mm- to cm-sized cavities, and individuals are up to 1.2 mm in maximum dimension. The crystallography and mineral chemistry of McCrillisite are described. -from Authors

Canadian Mineralogist↗