Precious Metal Jewellery - what are "carats" and how does Hallmarking work?
Objects made from, or containing, precious metals are classified according to a number of legal and regulatory conditions.
CARATS or CARAT WEIGHT
In the case of gold, pure gold is classed as 24-carat gold. This means that 24 parts are pure, out of 24 parts total. No other metals or substances are added.
Gold is a soft and malleable metal, and is seldom used in 24-carat configuration as the item would be too delicate in most instances.
Jewellers generally add portions of other metals to gold in order to strengthen the item being made. Typically, we see items made in:-
- 18 Carat (18 out of 24 parts = gold)
- 14 Carat (14 out of 24 parts = gold)
- 10 Carat (10 out of 24 parts = gold)
- 9 Carat (9 out of 24 parts = gold)
In the case of silver, pure silver is classed as "999", meaning that 999 parts out of 1000 are pure silver. As with gold, pure silver is relatively soft, so jewellers add other metals to harden it.
Sterling silver must be 925 parts of pure silver out of 1000 parts total. Items can only be classified or described as Sterling Silver if they are Hallmarked, (This is a compulsory requirement if the silver content in the object exceeds 7.78 grams or more).
In the case of both Gold and Silver, hallmarks are official symbols that identity the metal content, the manufacturer and the assay office that regulates that manufacturer, and in most cases, the date/year of manufacture.