Scheme Summary
Scheme Summary
Note: this list is not exhaustive. See us for additional requirements.
LabWest Digest Codes and Detection Limits
Sample Preparation (PREP)
Our sample preparation is designed to handle low-grade materials without cross-contamination.
Samples are dried, crushed (~2mm) and rotary divided where required. Pulverisation is undertaken by LM1 mill, and bowls are barren-washed after each sample.
Pulverisation in non-ferrous heads is available.
Gold (WAR)
Our low-detection gold technique (WAR) has been developed in-house to offer excellent recovery and signal discrimination in regolith materials, whilst minimising potential for cross contamination.
A 25 or 40g portion of pulverised sample is analysed for gold content using aqua-regia digestion, with determination by ICP-MS to achieve high recovery and low detection limits (0.5ppb).
A range of common pathfinder elements can also be determined by ICP-MS from the WAR leach. This should be considered a partial leach for these additional elements.
Multi-Element Analysis (MAR)
The MAR technique is designed for analysis of regolith materials for gold and base metals exploration.
The sample material is digested in aqua-regia under high pressure and temperature in microwave apparatus, with determination of analytes by ICP-MS/ICP-OES.
Pulverisation in non-ferrous heads is available.
Multi-Element Analysis With Rare-Earths (MMA)
The MMA technique is a microwave-assisted, HF-based digestion that effectively offers total recovery for all but the most refractory of minerals. This technique is well suited to materials such as core, rock-chip and stream sediments.
A portion of sample is digested in an HF-based acid mixture under high pressure and temperature in microwave apparatus for analysis, with determination of 61 elements including Rare-Earths by a combination of ICP-MS and ICP-OES.
Whole Rock Analysis (AF)
Samples are fused in an alkaline salt (lithium meta/tetraborate or sodium peroxide), and dissolved in nitric acid for determination of major rock-forming elements by ICP-OES and resistate traces by ICP-MS. Loss-on-ignition is included, and FeO and CO2 may be analysed by titration.
Partial Leach Analysis (PL)
Leachates are analysed for full multielement suites, including rare-earths, to low detection limit by ICP-MS and ICP-OES.
Examples of leaches performed:
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Water
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Sodium Acetate
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Sodium Pyrophosphate
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Weak Hydroxylamine Hydrochloride (0.1M)
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Strong Hydroxylamine Hydrochloride (0.25M)
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Chelating CN-based leach
Bio-Geochemical Analysis (MSA)
Microwave digestion apparatus offers complete sample decomposition under high temperature and pressure, elimination of cross-contamination and retention of volatile analytes.
Excellent detection limits are obtained for biological materials through the use of current-generation ICP-Mass Spectrometry for the determination of 64 analytes.
Whole-Rock Analysis For Researchers
A lithogeochemical characterisation package for research purposes.
Samples are analysed by a combination of alkaline fusion (for high field-strength and resistate elements) and HF/Multiacid microwave digestions followed by determination by ICP-OES and ICP-MS to give full analysis of component metallic elements. Carbon dioxide content is analysed by gas evolution or titration, and LOI is performed gravimetrically. FeO is determined titrimetrically.
Major rock-forming oxides, base metals, traces, volatile pathfinders, and rare-earth elements are reported, along with carbon dioxide and LOI.