State of Alaska Alaska | Natural Resources DNR | Geological & Geophysical Surveys DGGS | Geochemistry Geochem

Sample Detail

Sample Number Ci21411
Project Alaska strategic and critical minerals assessment project

Sample Documentation

Analyses [Download All]

Reference Number FA12138644
Reference Date 2012-12-01
Citation RDF 2014-7
Laboratory ALS Minerals
Description Historic geochemical samples from the DGGS, U.S. Geological Survey, and U.S. Bureau of Mines (USBM) archives were re-analyzed by DGGS using modern, quantitative, geochemical-analytical methods. Sample pulps were retrieved, examined, and split by DGGS staff into aliquots needed for the analyses. Splits of pulps were submitted to ALS Minerals Laboratories (ALS) for analysis. Where pulps were unavailable, coarse-reject material was prepped by ALS using the following method: coarse-reject samples were pulverized at ALS using flying disk or ring and puck style, low chrome, steel grinding mills. A sample split or total sample up to 250 g is pulverized, with 85 percent of the resulting material passing through a screen of 75 microns. Method PGM-ICP23: Pt, Pd, Au, 30-gram, FA-ICP-AES; Method: ME-MS81 38-element, fusion, ICP-MS; Method: ME-ICP61 33-element, 4-acid, ICP-AES; Samples with elements (Ag, Au, Cu, Pb, or Zn) above the detection limits in the analytical methods described above were re-analyzed using method: ME-OG62 Ore-grade elements, 4-acid, ICP-AES. Samples with gold (Au) above the detection limits in analytical method ME-OG62 were re-analyzed using method Au-GRAV21: Au, 30-g, FA
Sample Type pan concentrate

Reference Number OFR31-85-2
Citation OFR 31-85
Laboratory U.S. Bureau of Mines Reno Research Center
Description 60 pan concentrate samples were collected across three field seasons: Samples with the prefix "Ci" and "Be" were collected by the US Bureau of Mines in 1983 and 1977 respectively; samples with the prefix CP were collected by Union Carbide. Pan Concentrates were collected with a 14-inch pan heap-filled and panned until nearly all low-specific gravity minerals were removed. For samples with the Ci prefix, the concentrate was air-dried, weighed, and pulverized for analysis. Pan concentrate samples with the Ci prefix were analyzed for concentrations of Sn, W, Nb, and Ta using X-ray fluorescence analysis. Pan concentrate samples with the Be prefix were analyzed for Cu, Pb, Zn, Mo, and W using atomic absorption analysis and for a suite of elements using semiquantitative spectrography. Pan concentrate samples with the CP prefix were analyzed for Ag, Cu, Mo, Pb, and Zn using atomic absorption analysis and for W using colorimetry.
Sample Type pan concentrate