What is Sterling SIlver?
Sterling silver (SS) must be at least 92.5% silver. The 7.5% alloy in SS is made up largely of copper (there might be a bit of another proprietary metal formula that the manufacturer uses to make it stronger, but we are not privy to the formula). It does not contain nickel in the 7.5% alloy that makes up 925 silver.
The addition of copper to pure silver serves several purposes. First, it increases the strength and durability of the metal, making it more suitable for everyday use – it is relatively soft and malleable, so the addition of copper enhances its structural integrity. Second, the copper content helps prevent tarnishing, which is a natural process that occurs when silver reacts with sulphur compounds in the air.