Surface Exploration GeoChemistry
Surface exploration necessitates careful sample handling and meticulous analysis, to ensure that small anomalies are discriminated and contamination is avoided. LabWest specialises in these areas and can assist you in determining the best approach for your samples.
GOLD EXPLORATION GEOCHEMISTRY
Our techniques for detection of gold are optimised for surface and near-surface exploration, where anomalies can be very small, and signal discrimination is paramount.
Processes are designed to minimise the possibility of contamination, from barren-washing of pulveriser bowls during sample preparation through to use of disposable vessels for all stages of digestion and analysis.
Current-generation ICP-mass spectrometry (ICPMS) is used for elemental determination, yielding reliable sub-part per billion detection limits.
Separation and collection of ultrafine (< 2 µm) fraction from soil samples. Analysis of 40-element suite on the fine fraction, plus pH, salinity (conductivity), particle size distribution, and clay mineralogy (ASD).
LabWest Code UFF+: Collection and analysis of <2µm fraction for all UFF+ parameters.
Our aqua-regia extraction was purpose-designed for geochemical exploration. The recovery of gold from regolith materials is excellent, and the technique is very sensitive. Sample masses of 25g or 40g are typically taken from the pulverised or screened bulk for analysis.
LabWest Codes WAR-25 and WAR-40 Au – 0.5ppb detection limit.
Oxidised surface materials such as stream sediments containing free gold, are well suited to cyanide extraction techniques. The use of a larger sample (500g) ameliorates nugget-effect to a large degree. Cyanide dissolves very little of the surrounding matrix, and excellent detection limits can be obtained.
LabWest Code WCN-500: 500-4000g cyanide leach
A range of partial leaches are available, from weak (eg. ammonium acetate) to strong (eg. aqua-regia). Please see our Partial Leaches page for details.