Long experience in the analyses of precious metals with diverse matrices and concentration levels
Labtium provides traditional Fire assay for the analysis of Au, Ag, Pd and Pt in mineral process samples. The analyses can be done for all grades of material. Depending on the grade and elements the AAS, ICP-OES or gravimetric finish is used. Feed and tailing samples are analysed using Fire assay and AAS or ICP-OES finish (Method 740A/P). Low grade concentrates e.g. flotation concentrates are analysed using Fire assay and gravimetric finish (Method 740G). High grade concentrates are analysed using high precision rotary splitting, Fire assay and gravimetric finish (Method 741G). Labtium specialists will help select the right method for your use.
Silver analyses can be done also with aqua regia digestion and instrumental determination by FAAS or ICP-OES.
For processing of gold where CIP and CIL techniques are used Labtium can provide Au carbon-analyses. Additional elements such as Ag, As, Cd, Co, Cu, Ni, Pb and Zn can also be analysed.
Screen Fire assay can be done to evaluate the amount of coarse gold in the desired material. A 0.5 kg subsample is sieved with a 125 µm sieve and both fractions are weighed. Fire assay is done on the +125 µm-fraction and duplicate fire assay on the -125 µm-fraction. Weighted concentrations of gold are calculated.
Free metallic gold and silver can be analysed in process samples using cyanide leach (Method 236A). By combining with the analysis of leaching tailings by Fire assay both free and refractory gold can be determined. Moreover, sequential, diagnostic leaches and other chemical phase analyses methods can be used.