Not all countries use hallmarks. A hallmark is a system of verification of the fineness of a metal and can also include a maker’s mark and a date stamp. France and England have the oldest hallmarking schemes while countries like Australia and the USA have none, despite attempts to introduce them.
One early attempt of hallmarking in Australia was in 1889 when the Manufacturing Jewellers Association of Victoria agreed on a scheme. The Association members applied three guarantees to their work, the maker’s mark, a quality mark in carats, and a symbol. The symbol for 9ct was a sheaf of wheat, for 12ct a pick and shovel, 15ct a hung sheep and for 18ct a sailing ship. While the scheme eventually spread to the rest of the Commonwealth of Australia, its use petered out during the 1920s. In Australia today, members of the Gold and Silversmiths Guild of Australia have a marking system.
In 1906, the USA did introduce a voluntary scheme which permits a jeweler to put a purity mark and from 1961, this must be accompanied by a maker’s mark. There is an international convention on hallmarking, the Vienna Convention on the Control of the Fineness and the Hallmarking of Precious Metal Objects, comprising approximately 18 European countries, which uses a common control mark. Member countries will allow articles, which have been marked with the Common Control Mark (CCM) and which are of a legally recognised fineness, to enter their territory without additional control or marking.
Antique jewellery is most commonly made out of 18ct, 15ct, and 9ct but you will also see 14ct, 12ct and 10ct. In the UK, up until 1854, the official gold standard for hallmarking gold was 18ct and 22ct, but other gold carats were still used. From 1854, the gold standard in the UK was amended to included 15ct, 12ct and 9ct. In 1932, the 12ct and 15ct standards for gold in the UK were abolished in favor of the 14ct mark. In the US, 14kt gold was popular.
Most of the hallmarked antique jewellery I see has been made in the UK and has been hallmarked through one of the UK Assay Offices – Birmingham, Sheffield, London, Edinburgh, Chester, Glasgow, Exeter, Newcastle, Dublin, Chester, Glasgow (note that only the first four assay offices remain). The word ‘hallmark’ arises from the fact that in 1478, makers of items of gold or silver had to bring them to be marked by an assayer at the Goldsmith’s Hall.
Antique jewellery in the UK did not have to be hallmarked. In 1738, the Plate Offences Act exempted from hallmarking ‘all jeweller’s works’ unless it was a mourning ring (compulsory from 1784) or a wedding ring (from 1855). It applied to gold and silver. Rings with gems, signet rings and other types of dress rings were exempted from hallmarking as were chains like watch chains, Albert chains, necklace chains, key and fob chains and seals. Lockets, brooches, necklace beads, items set with gems and paste and small works set with amber, and filigree work were also exempted. Of course, voluntary hallmarking was possible which is why we see some hallmarked pieces. Hallmarking is now compulsory in the UK.