Sampling

Small amounts of metal are very carefully scraped or cut from articles to produce laboratory sized samples for assay.

Many articles are received in the unfinished state and in the case of articles which are scraped to remove the metal, the scraping marks are easily removed by the manufacturer in subsequent finishing operations.

Some articles in the form of stampings and castings allow the removal of surplus material by small cuttings to produce samples.

The number of samples taken depends on the quantity of articles in the parcel and also the nature of the articles, the number of parts to an article and the different materials from which they have been made; for example, castings, sheet, wire, rod or tube.

Separate samples have to be taken as far as is practical from each category of articles (rings, brooches, earrings, bracelets etc) and each type of material. Composite samples can be obtained from groups of articles of the same category, pattern and type of material.