What is geochemical/assay?
Geological materials which can be analyzed include rocks, soils, organic matter, water and heavy minerals.
Geochemical Assay is carried out using ICP-AES, ICP-MS, and/or Atomic Absorption with a variety of digestion & fusion techniques. With these methods, we are able to report up to 51 elements at the Ultra Trace Level, but also able to detect concentrations of up to 100% of some elements.
Geochemical Analytical Services
What digestion is best for the sample?
Aqua Regia Digestion
Aqua Regia uses a mixture of Hydrochloric and Nitric acids which act as an oxidizing agent to dissolve most oxide, sulfide and carbonate materials. This digestion will yeild semi-quantitative results as some of the more resistant minerals including silicates are only partially dissolved.
Four-Acid or ‘near total’ digestion uses a combination of Hydrochloric, Nitric, Perchloric and Hydrofluoric acids. Only the most highly resistant minerals will not be dissolved using this type of digestion.
Lithium Metaborate Fusion
Pulverized samples are fused at a temperature of 1000 Celsius using Lithium metaborate and then the resulting melt is digested in a weak Nitric acid solution. This high temperature procedure is capable to detect thirteen (13) common rock-forming elements and is reported as oxides.
Sodium Peroxide Fusion
Sodium peroxide fusion is effective at decomposing sulfides and arsenides, and will render many refractory minerals soluble. The fusion temperature is lower than that of a Lithium metaborate fusion, which means that hydride elements are not volatilized when using Sodium peroxide fusion.