Analytical Suite Metadata
Chemex (lake and stream sediment) FA-NA (Au) + Wt -Au (variable d.l.= 1 for 10g sample or 2 ppm for 5g sample)
Chemex, lake and stream sediment; fire assay pre-concentration, neutron-activation / gamma ray spectroscopy (gold) + weight -Gold has variable detection limit. d.l.= 1ppb for 10g samples or 2 ppb for 5g samples
Gold was usually determined on a 10 g sediment sample; depending on the amount of sample available, lesser weights were sometimes used. This resulted in a variable detection limit: 2 ppb for a 5 g sample, 1 ppb for a 10 g sample... The sample was fused to produce a lead button, collecting any gold in the sample, which was cupelled in a muffle furnace to produce a silver (dore) bead. The silver beads were irradiated in a neutron flux for one hour, cooled for four hours, and counted by gamma ray spectrometry. Calibration was carried out using standard and blank beads.
Sample material: solid
Sample weight: unstated
Associated Analytical Packages:
- Date modified: