Gold Analysis

Fire Assay

For decades Fire Assay has been the standard method of analysis in the gold industry.   The fire assay method involves:

• Crushing and pulverising samples
• Fluxing and fusion of the sample at high temperatures
• Separation of the slag from the lead precious metals-containing button
• Cupellation – separating precious metals from the lead
• Analysis of the precious metals content

Photon Assay

A new method of gold analysis has emerged known as photon assay.  The technology which originated from CSIRO in Australia is now being rolled out to the gold industry by an ASX listed company.  In this process, crushed samples are placed into plastic jars, for gold analysis by the photon assay system.

Our products for gold analysis

XRF Scientific offer laboratory jaw crushers for high performance processing of gold samples.  Large samples of up to 110mm can be crushed down to 2mm in a single processing step.  Optional splitters (sample dividers) are available which will take from the total sample a lesser weight representative sample, which can then be analysed for gold.  The below outlines the method of using our Orbis smart crushing systems in preparing gold samples:

• Weigh the total sample on the weighing station
• Input into the PLC the final split sample required
• Load the sample into the hopper. Loading into the hopper can be assisted with an optional lifter device
• Samples are crushed to the desired fraction as set by the user e.g. 90% passing 2mm
• A feeder transfers the sample from the crusher outlet to the attached splitter
• The splitter creates a representative sample based on the weight input into the PLC, with the remainer sent to waste. The sample splitter comes as a Rotary Sample Divider (RSD) or Liner Sample Divider (LSD)
• For photon assay users, the split sample can be dosed automatically into the required plastic jar, in duplicates

For fire assay users we offer a range of pulverisers and pulveriser bowl consumables, for further processing after crushing.