The choice of sample fraction to be analysed must be done based on the objectives of the project and targeted elements
For soil samples e.g. till, we recommend drying at 70 °C (Method 10) and sieving to less than < 0.06 mm fraction (Method 24). If mercury or other volatile components are to be determined, lower drying temperatures must be used. High drying temperatures may also cause oxidation of some minerals. Other sieve fractions such as < 0.125 < 0.25 < 0.5 mm can be used upon client’s request. When requesting sieving, please indicate the fraction to be analysed. If coarse sieve fractions are used for analysis, additional pulverizing is regularly required (Method 40). Optionally several fractions can be collected during sieving using different sieves on top of each other (e.g. <0.06, 0.06-0.5, 0.5-2.0, >2.0mm). These different fractions can be delivered to client for additional studies – e.g additional analyses or defining bedrock type of parent material in >2mm fraction.
For some purposes, the entire soil sample such as weathered bedrock or a coarse sieved fraction of the sample must also be crushed and/or pulverised.
The client is obliged to inform Labtium for any observed components in the samples causing potential occupational health e.g. asbestos, radioactivity or environmental risk beyond the normal geolaboratory operation. Labtium is entitled to cease the processing of the samples if any of these risks are observed until the process is duly modified to eliminate the risks.