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

Sample Detail

Sample Number 06MBW163A
Project Casadapega River Bluff area, Solomon Quadrangle

Sample Documentation

Analyses [Download All]

Reference Number FA06104214
Reference Date 2006-11-14
Citation RDF 2007-4
Laboratory ALS Chemex
Description 205 rock samples were crushed with a Terminator jaw crusher with chrome steel alloy plates so that at least 70 percent of the material passed through a -10 (2 mm) mesh screen. Representative aliquots of 250 grams and 30 grams each were taken using a stainless steel riffle splitter. These samples were then pulverized in a chrome steel ring mill so that 85 percent of the sample passed through a -200 (75 micron) mesh screen. Most trace-element analyses were performed on the 250 gram split while gold analyses were performed on the 30 gram representative split. Initially, all samples were assayed for gold by Atomic Absorption Spectroscopy following a fire assay fusion. Samples containing greater than 10,000 ppb gold were also assayed by Gravimetric finish following a fire assay fusion. All samples were assayed for mercury by Inductively Coupled Plasma - Atomic Emission Spectroscopy after Aqua Regia digestion and by Atomic Absorption Spectroscopy after Aqua Regia digestion/Cold Vapor. High-grade copper samples were assayed by AAS. All other trace element geochemical analyses were performed by Inductively Coupled Plasma - Atomic Emission Spectroscopy methods following Aqua Regia digestion. This method of digestion is possibly incomplete for some elements and may result in lower analytical results for certain elements. See publication for a listing of these elements.
Sample Type rock