The fineness of a precious metal refers to the ratio by weight of the primary metal to any added base metals or impurities Various ways of expressing fineness have been used and two remain in common use: millesimal fineness (1/1000 in weight) or Karats (1/24 in weight). This way, pure gold has 24 karats (24k) and 1000.
Gold millesimal fineness is usually rounded to a three figure number, particularly where used as a hallmark:
Sterling Silver has a millesimal fineness of 925. The sterling silver alloy is 92.5% pure silver and 7.5 per cent copper or other metals, that doesn`t affect the alloy color.
Platinum has a naturally white lustre that does not fade or tarnish. Because it is generally 95% pure, platinum jewellery is hypo-allergenic. It is 60% heavier than gold and is exceptionally durable.
All our wedding rings has some marks called hallmarks, an official mark struck on jewells.