Gold Analysis

Precession laboratory testing to determine the quality of your gold samples. Laboratory analysis of gold is generally carried out through a fire assay process to isolate the precious metals and followed by gravimetry or atomic absorption spectrometry (FAAS) to determine sample concentrations.

ARCHER SLEDGE preferred method of gold analysis is initially conducted through fire assay, a method that has existed for many centuries but is now undertaken in a streamlined process. It is essential to carry out the process in a highly-disciplined way to ensure accuracy. ARCHER SLEDGE laboratory technicians are greatly experienced in the techniques and processes and their analysis is regarded as outstanding in the industry.

Samples, generally in powder form, are mixed with a fluxing agent to which is added lead oxides. Furnace heating fuses the sample and begins to separate out precious metals from the sample matrix. The next stage is to separate out the collector (the lead) from the precious metals by the cupellation process. The lead button recovered from the fusion process is placed on a cupel and heated in a furnace. The cupel absorbs the lead leaving a bead for further analysis.

A range of highly accurate techniques may then be used to determine the concentration of gold in the original sample. These include Gravimetry, Flame Atomic Absorption Spectrometry (FAAS), and Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES).

Although fire assay is a well-established way of isolating the precious metal material, it is essential that it is carried out with meticulous care. Inspectorate regularly carries out round robin surveys to ensure that there is consistency of results across its gold analysis facilities worldwide.

International standards

ARCHER SLEDGE undertakes gold analysis in accordance with international standards such as ISO 10378