Exploration Geochemistry

Bureau Veritas offers the widest array of multi-element packages to suit the needs and budgets of all exploration teams. Analysis consists typically of two stages; The first, comprising extraction of the desired elements followed by the second stage of element determination by instrumental analysis.

Extraction can be partial to measure only non-resistive elements of or the extraction can be total to measure the total abundance of the elements from all minerals in the sample.

Our laboratories are renowned for the use of cutting edge technologies to obtain the low levels of detection needed to meet exploration geochemical requirements.

Summary

our services :

Aqua Regia Digest & ICP

An aqua regia digest is particularly useful for exploration programs as it offers an economical and effective means of evaluating common key pathfinder minerals.  

Aqua regia digests are suitable for dissolution of carbonate, oxide and sulfide and provides a semi-quantitative dissolution of precious and base metals. The aqua regia digest is not effective in the complete break down major rock forming minerals (e.g. silicates) and resistive metals; however this digestion limits the loss of volatile elements which are often of importance in some deposits.

Disposable digestion vessels are used to eliminate contamination from the reuse of beakers.

Fusion Techniques

Fusion techniques are required for precious metal analysis and complete characterization of geological material. A flux material is added to the sample to either liberate or bind certain components before analysis. 

In the case of whole rock characterization, an added flux reacts with the rock forming minerals enabling quantitative analysis by either XRF, laser ablation or ICP (following an acid dissolution). Meanwhile maintaining detection limits comparable to traditional multi-acid digestion methods. Fusion followed by XRF or laser ablation finishes also offers safety and environmental advantages as no acids are used in digestion, and it is fast and repeatable.

Laser Ablation ICP-MS

Bureau Veritas Laser Ablation ICP-MS and XRF analysis is designed to provide a single, cost effective method for total whole rock characterization. The method involves a high productivity robotic fusion, followed by XRF and state of the art laser ablation technology on the fused bead to provide a fully extracted quantitative analysis for most elements. 

The combination of XRF and LA-ICP-MS provides a package with lower detection limits comparable to traditional acid digestion methods, and upper limits of 100%. The technique offers safety and environmental advantages as there are no acids used in digestion, and it is fast and repeatable.

Lithogeochemistry

Lithogeochemical methods employ fusion techniques to completely decompose even the most refractory matrices to provide total element concentrations. These methods account for structural water and provide quantitative results for silicon and are therefore the only methods that provide data suitable for plotting whole rock classification diagrams and molar element ratio studies. ICP-ES, ICP-MS, LA-ICP-MS and XRF options are available to suit all elements, concentration ranges, professional preferences

Mixed Acid Digest & ICP

Bureau Veritas offers a wide variety of multi-element technique for your exploration, research definition, mine-site and metallurgical requirements.

Care and attention begin prior to any sample collection. Rock and core samples are dried then prepared by particle size reduction to produce a homogeneous sub-sample which is representative of the original sample. 

Mixed Acid Digests offers a strong dissolution of most minerals with a choice of either ICP-ES or ICP-MS analysis. Acid attacks using nitric, perchloric and hydrofluoric acids breakdown many minerals, including silicates.

The highly cost effective technique provides near-total determinations for most elements, with low to very low detection limits. Low levels of rare earths may also be quantitatively recovered. More resistant metals such as Chrome Titanium, Magnesium, Zirconium and Tungsten are only partially attacked.

Vegetation Analysis

Root systems of plants draw in water, which contain elements from the interaction with bedrock and overburden soils/sediments. Depending on the size of the plant, the root system and the particular species this up-take of water by the plant can provide the geologist with a significant geochemical signature when certain parts of the plant are sampled.

Bureau Veritas offers two preparation methods for vegetation samples:

  • Samples are dried, macerated, and the material is digested with aqua regia, or
  • Samples are dried, ashed, and the ashed material is digested with aqua regia. 

Ashing is the preferred method if determination of precious metals and other low level elements are required. Vegetation analysis includes BV’s ultra-trace ICP-MS package, which provides the lowest detection limits available.

X-Ray Fluorescence

X-Ray Fluorescence (XRF) fusion techniques are suitable for the analysis of most mineralogical ores, metallurgical products and complex matrices, particularly where total analysis with high precision is required for major elements.  

Our laboratory in Perth, Australia, boasts the largest XRF facility in the world utilising robotically serviced fusion machines and automated XRF Instruments. All other Bureau Veritas sites use similar methodology and equipment and draw on the expertise available for technical support.

Bureau Veritas offers a number of analytical packages for routine analysis.