Refers to the gold content
in 1,000 parts of a bar or alloy.
A normal ‘good delivery bar’ is 995
parts pure gold and five parts other metals or impurities. The gold market accepts
bars only up to a purity of 999.9 (four nines)
but in electronics a bonding wire of 999.99
(five nines) is used. The fineness is usually stamped along with the refiner’s
or assayer’s mark.
Fineness is also expressed in carats, especially
in the jewellery trade.