The traditional sampling methods for assay require a tiny sample to be scraped from items in the batch, for testing by cupellation for gold, titration for silver or ICP for platinum and palladium.
It also has the benefit of being quicker and more environmentally friendly than the energy and chemical hungry traditional methods of cupellation and titration, which are still used as reference methods.
In the case of the latter, it is not clear how the stated definition of gold as that "which resists cupellation
and is insoluble in aqua fortis" provides one with the means to deduce further properties of gold.
This product would then be carried to nearby hillsides, or seaside cliffs (both good for catching the winds to further fan the ovens) for roasting, and separation of metallic silver by cupellation
The slag is discarded while the button is subjected to cupellation
, during which the precious metals are separated from the lead and other metallic impurities during a melting process which takes place in a flat porous dish made of a refractory material called cupel, onto which a blast of hot air is directed in a special furnace.
After lengthy examination, Newmont found that centuries-old fusion and cupellation
procedures used in fire assaying weren't easily adaptable to automation; these steps are the only major procedures still performed as a fully manual operation.
Such samples may require sophisticated new techniques, but for gold and silver the most accurate methods remain traditional cupellation
and titration, which are still the referee methods.
In most cases, they eliminate the expensive and destructive cupellation
According to Nriagu (1985), cupellation
of silver is the "oldest quantitative chemical process known to mankind," probably dating to 4,000 B.
Gold and silver reported together as dore metal after cupellation
Refined lead production was 5,612 t, and 934 kg of silver produced by cupellation
was sent for refining to the precious metals plant.
An accurate method of determining gold content is the historic cupellation
method but the clear disadvantages of this method left a gap in the market for Fischer to apply their X-ray fluorescence expertise and present what has become an extremely cost efficient system for jewellery and precious metals analysis.
PHOTO : An assayer placing bone-ash cupels in an electric cupellation