How we process scrap metals
These are usually composed of several different metals alloyed in various proportions - dental alloys for example might contain any or all of gold, palladium, platinum, ruthenium, silver combined with one or several base metals to any of several dozen different formulations.
In order to ensure that you receive the maximum possible value for scrap it is vital that these mixed alloys are melted correctly and economically and to do this the induction process is used.
Not only does induction melting produce very high temperatures but in doing so the induced current when correctly operated results in a homogenous molten pour into bar or cone form.
The bar or cone is then separated from its flux layer for cleaning. Both this and the removed flux are examined to ensure total separation has occurred - if not this stage of the process is repeated until correct.
HOW WE PROCESS DUST EXTRACTOR BAGS, WIPES, ETC
These materials require primary burning to break down the material, oxidising the non-metallics: to do this whilst safeguarding the metallic content it is essential that scrap is loaded and burnt at the correct rate and at the correct temperatures.
After oxidisation the resultant materials require crushing and sieving to reduce the particle size below a minimum for melting: because the material now contains oxidised non-metallics it is important that the correct fluxes mixed in the correct proportions are utilised during the melting stage.
HOW WE ASSAY
Full metal assays are obtained by ICP [Inductionally coupled plasma emission spectrometry] of bar and cone drillings or XRF (x-ray readings of pelleted samples) and, where applicable by NSADT (a dissolution technique using a mixture of acids).
At each stage of processing weights have been taken and it is the weight of the bar or cone related to assay results that determine how much of each of the precious metals is present.
