What does a metal's "purity percentage" actually mean in practical terms?
Short answer: Purity percentage refers to how much of a given piece of scrap is the actual base metal versus other materials, alloying elements, or contamination — for example, "99% copper" means roughly 99% of the material by weight is copper, with the remaining 1% being other elements or impurities, and higher purity generally commands a higher price since it requires less processing to reach usable raw material.
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List Free →Why purity is measured by weight, not appearance
A piece of metal can look clean and shiny while still containing meaningful impurities at a chemical level — purity is determined through actual testing and assay, not visual inspection, which is why buyers often test or certify material rather than relying on appearance alone.
Why purity affects price so directly
Lower purity material requires additional refining to reach a usable state, and that extra processing cost is reflected in a lower price paid to the seller — the relationship between purity and price is essentially about who bears the cost of getting to a pure, usable end product.
Why purity standards vary by metal
Different metals have different typical purity benchmarks and testing methods — what counts as “high purity” copper differs numerically and in testing method from what counts as high purity for aluminium or other metals.
How ScrapTrade Fits In
ScrapTrade lets you describe your material’s known purity and condition clearly, helping match you with buyers who understand exactly what you’re offering.
Understanding grading and purity terminology helps you know what your material is actually worth. ScrapTrade connects verified buyers and sellers with transparent weighing and escrow-protected payments.
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