Fire assay is an analytical techmique usedin the determinaion of the qualty and purly of gold. This method dates back to ancient imes but has been refned and improved upon ove!the years.ire asay is an analyticaltechnique used inthe determinaion of the qualty and puityof gold. This method dates backto ancientimes buthas been refined and improvedupon over the years.
Fire assay is an analyticaltechnique used inthe determination of the qualty and purity ofgold. This method dates back to ancient imes but has been refined and improved upon overthe years.
Fire Assay Process
Sample preparation
With Flux Dispensing and Mixing Devices, fire assay dosing and mixing can beachieved in a repeatable, traceable and operator-safe manner, while alsoincreasing laboratory productivity.
Fusion
The pulverized sample is weighed and mixed with a fluxing agent. Lead isadded as a collector. The sample is then heated in a fumace at about 1000degrees. During this process, the lead in the flux melts and collects the preciousmetals as it forms a low-melting-point alloy with them.
Cupellation
Following the fusion, the molten lead and the precious metals are placed in aporous cupel and reheated. The lead is absorbed by the cupel, leaving behinda bead composed of the precious metals. This is a critical step for purifying theprecious metals from the lead.
Weighing and Analysis
The resulting metal bead is weighed to determine the concentration of preciousmetals in the original sample. Further tests may be conducted to ascertain theexact content of gold and silver.
