Scientist sieving a sample of gold placer tailings to analyze for critical mineral contents in Uhler Creek, a tributary to the South Fork of the Forty Mile River in east central Alaska.
Critical minerals are essential to the U.S. economy and national security, have a supply chain that is vulnerable to disruption, and serve an essential function in the manufacturing of many products. Often, critical minerals are found as co- or by-products in deposits mined for precious or base metals. The projects described here develop an interdisciplinary (geological, societal, ecological) and integrated assessment for above ground resources at past-producing and current mine sites in Alaska. The potential presence of critical minerals in the above-ground materials remaining from past mineral production is due to factors such as lack of a prior need, lack of identification, previously unfavorable economic extraction of the commodity, and alternative sources of the commodity. In Alaska, there is particular interest in a volumetric inventory of critical mineral resources present in historic placer districts. Together the following projects will investigate and inform the viability of processing materials that have been previously mined for other resources.
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Goals:
- Determine the relative enrichment of critical minerals in placer resources relative to natural, unprocessed stream gravel
- Investigate critical mineral concentrations and host mineral phases in different size fractions of placer gravel to inform elemental concentration and extraction processes
- Delineate and incorporate ecological and societal benefit and risk factors in evaluations of critical mineral resource potential
Projects:
Critical Minerals in Alaska Placer Deposits and southeast Alaska Mineral Systems
Critical Minerals in Alaska Placer Deposits and southeast Alaska Mineral Systems
Critical Minerals in Alaska Placer Deposits and southeast Alaska Mineral Systems
Multi-Resource Integrated Assessments (MRIA) and the Critical-Mineral Potential of Legacy Mine Above-Ground Resources
Multi-Resource Integrated Assessments (MRIA) and the Critical-Mineral Potential of Legacy Mine Above-Ground Resources
Multi-Resource Integrated Assessments (MRIA) and the Critical-Mineral Potential of Legacy Mine Above-Ground Resources
Uhler Creek
Scientist sieving a sample of gold placer tailings to analyze for critical mineral contents in Uhler Creek, a tributary to the South Fork of the Forty Mile River in east central Alaska.
Cassiterite Creek
Scientist sieving a sample of tin placer tailings in Cassiterite Creek on the western Seward Peninsula.
Scientist sieving a sample of tin placer tailings in Cassiterite Creek on the western Seward Peninsula.
Kougarok River
Kougarok River at the confluence with Taylor Creek, Alaska. Large volume of gold placer tailings that contain critical minerals on the Kougarok River on the western Seward Peninsula.
Kougarok River at the confluence with Taylor Creek, Alaska. Large volume of gold placer tailings that contain critical minerals on the Kougarok River on the western Seward Peninsula.
Dredge
Historic dredge and large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River near Goodnews Bay, Alaska. Dragline-sluice tailings are in the foreground, stacked dredge tailings are in the background near the dredge.
Historic dredge and large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River near Goodnews Bay, Alaska. Dragline-sluice tailings are in the foreground, stacked dredge tailings are in the background near the dredge.
Salmon River tailings
Large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River south of Goodnews Bay, Alaska.
Large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River south of Goodnews Bay, Alaska.
Clear Creek
Scientists collecting a 1/5 yard composite sample in blue 5-gallon buckets from gold placer tailings to analyze for critical mineral contents in Clear Creek, in the Zane Hills north central Alaska.
Scientists collecting a 1/5 yard composite sample in blue 5-gallon buckets from gold placer tailings to analyze for critical mineral contents in Clear Creek, in the Zane Hills north central Alaska.
Chicken Creek
Scientist checking a gold pan for gold and critical minerals in placer tailings on lower Chicken Creek near Flat, Alaska, in the Kuskokwim Mountains. A sample was collected from legacy gold placer tailings at this site and 7 others in the Flat mining district to determine the critical mineral contents of tailings from which only gold has been removed.
Scientist checking a gold pan for gold and critical minerals in placer tailings on lower Chicken Creek near Flat, Alaska, in the Kuskokwim Mountains. A sample was collected from legacy gold placer tailings at this site and 7 others in the Flat mining district to determine the critical mineral contents of tailings from which only gold has been removed.
Uhler Creek
Scientist sieving a sample of gold placer tailings to analyze for critical mineral contents in Uhler Creek, a tributary to the South Fork of the Forty Mile River in east central Alaska.
Scientist sieving a sample of gold placer tailings to analyze for critical mineral contents in Uhler Creek, a tributary to the South Fork of the Forty Mile River in east central Alaska.
Cassiterite Creek
Scientist sieving a sample of tin placer tailings in Cassiterite Creek on the western Seward Peninsula.
Scientist sieving a sample of tin placer tailings in Cassiterite Creek on the western Seward Peninsula.
Kougarok River
Kougarok River at the confluence with Taylor Creek, Alaska. Large volume of gold placer tailings that contain critical minerals on the Kougarok River on the western Seward Peninsula.
Kougarok River at the confluence with Taylor Creek, Alaska. Large volume of gold placer tailings that contain critical minerals on the Kougarok River on the western Seward Peninsula.
Dredge
Historic dredge and large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River near Goodnews Bay, Alaska. Dragline-sluice tailings are in the foreground, stacked dredge tailings are in the background near the dredge.
Historic dredge and large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River near Goodnews Bay, Alaska. Dragline-sluice tailings are in the foreground, stacked dredge tailings are in the background near the dredge.
Salmon River tailings
Large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River south of Goodnews Bay, Alaska.
Large volume of gold placer tailings that contain platinum group and chromium critical minerals on the Salmon River south of Goodnews Bay, Alaska.
Clear Creek
Scientists collecting a 1/5 yard composite sample in blue 5-gallon buckets from gold placer tailings to analyze for critical mineral contents in Clear Creek, in the Zane Hills north central Alaska.
Scientists collecting a 1/5 yard composite sample in blue 5-gallon buckets from gold placer tailings to analyze for critical mineral contents in Clear Creek, in the Zane Hills north central Alaska.
Chicken Creek
Scientist checking a gold pan for gold and critical minerals in placer tailings on lower Chicken Creek near Flat, Alaska, in the Kuskokwim Mountains. A sample was collected from legacy gold placer tailings at this site and 7 others in the Flat mining district to determine the critical mineral contents of tailings from which only gold has been removed.
Scientist checking a gold pan for gold and critical minerals in placer tailings on lower Chicken Creek near Flat, Alaska, in the Kuskokwim Mountains. A sample was collected from legacy gold placer tailings at this site and 7 others in the Flat mining district to determine the critical mineral contents of tailings from which only gold has been removed.