Assaying Services

THE TESTING OF ALLOY TO DEFINE PRECISE CONFIRMATION OF PRECIOUS METAL CONTENT

We utilise the leading technology available to assay and confirm the precious metal content of articles presented for testing. We work with our customers to process the vast majority of assaying through non-destructive techniques.

For hallmarking requirements in particular, we select samples from every batch of work received and analyse utilising X-ray Fluorescence Spectrometry (XRF) machines.

We also test utilising more traditional methods such as cupellation (gold) and potentiometric titration (silver).

As well as detection of hazardous elements, we can also provide Melt & Assay – melting and confirmation of content of scrap precious metal – through the following methods:

 

GOLD ASSAYING

CUPELLATION (ISO 11426 / Accredited UKAS 17025)

  • This method requires gold, lead foil and silver. Samples are subjected to a furnace firing at 1100 degrees Celsius. A comparison of the weight of the pure gold with the weight of the original sample provides the degree of purity. An alternative method may be used depending upon the concentration of gold.

 

SILVER ASSAYING

POTENTIOMETRIC TECHNIQUES

  • These methods are used to determine silver in high grade bullion or metallic samples.

POTENTIOMETRIC ANALYSIS OF SILVER

  • Silver content determined following dissolution by a Potentiometric titration (following the principles of ISO 11427).