Purity

Purity refers to the proportion of fine metal - such as gold or silver - in a given product relative to other elements or alloys. In modern bullion production, the standard level of purity for gold and silver is 999/1000, meaning the product is composed of 99.9% fine metal. Some coins and bars are produced with even higher purities, up to 999.99/1000, although such levels require advanced refining techniques and are typically reserved for special issues.

It’s important to note that even at 999/1000, a metal is considered “pure,” as it is practically impossible to eliminate all trace elements. To achieve the precise fine weight stated, most coins and bars weigh slightly more than their declared weight to compensate for the presence of alloyed materials.

In addition, many coins are intentionally made from metal alloys for durability - especially historical coins or circulating legal tender. However, for a gold coin to qualify as investment-grade bullion in most jurisdictions, it must have a minimum fineness of 900/1000, according to international and tax-related standards.