What Does the Stamp Inside of a Ring Mean?

Jon Fife/CC-BY-SA 2.0

The stamp inside a ring, bracelet or other piece of jewelry is used by the manufacturer to indicate the manufacturer’s or designer’s name, the metal purity and type. Called hallmarks or assay marks, there are a very large number but in terms of valuation, the most important deal with metal type and purity.

Silver purity is given in a numerical code, which refers to its purity across a thousand parts.

  • 925 is sterling silver
  • May also appear as: S. Silver, sterling, SS or 925/1000
  • May be gold plated

Gold may be indicated as a karat weight, or K, or also as a numerical code referring to its purity over a thousand parts, based on pure gold being 24 karats.

  • 10K – 10 karats; 14K – 14 karats; 18K – 18 karats; 22K – 22 karats, or
  • 417 – 10 karats; 585 – 14 karats; 750 – 18 karats; 833 – 20 karats.
  • Platinum – the other precious metal – is indicated as Plat. or 950 Plat.

Other metals use varying formats to indicate type. Base metals hallmarks only indicate the type of metal and not its purity.

  • S.S. – stainless steel
  • G.F. – gold filled like a gold shell filled with a base metal
  • G.P. – gold plating over a base metal