catalogue descriptions and hallmarking

There is a lot of confusion concerning the sale of jewellery by auction, this is mainly due to the way in which jewellery is described in the catalogue.

Firstly, a mention about hallmarking. Hallmarks are governed by the UK hallmarking Act 1973 as amended. Items must not be sold in the UK as being wholly or partly made of gold, silver or platinum unless they are British Hallmarked, exempt or have a Convention Mark (an agreement between certain countries recognising a hallmarking standard).

Why do we say 'yellow metal' when the item has a British Hallmark?

Some of our vendors have instructed to use 'yellow metal' or 'white metal' to describe items that would otherwise be described in our catalogue as gold or platinum. Gemstones are also treated the same way. This is not to say that the items is not gold or the red stone is not a ruby. The vendor has left it up to the bidder to decide whether or not the items is indeed gold or base metal.

As with all items at auction it is up to the bidder to decide what the item is and how much they are willing to pay.

a guide to british hallmarking

British Hallmarks after 1998 consist of the following:

1. A Sponsor's or makers mark
2. The number of parts per thousand of pure metal ie gold, silver or platinum
3. An assay office mark, ie London, Birmingham, Sheffield, Edinburgh.
3. and a date letter (optional)

Example :

As from 1 January 2010, there are now four precious metals hallmarked in the UK. Along with Gold, Silver and Platinum, Palladium is now recognised.

A Dealers Notice showing hallmarking information is displayed in our sale room.

A pdf copy of the dealers notice is available here

Jewellery Weights and measures

Precious metals and gemstones use the following systems of weights.

1 ounce = 28.34952 grams (normal imperial weight)
1 troy ounce = 31.1035 grams (precious metal weights)

480 grains = 1 troy ounce
5760 grains = 1 troy pound

Carats are a measure of a diamonds weight not its size.
1 carat = 0.2 grams

1 carat = 100 points 

    Frank G Bowen Limited - 2 The Hitchcock Business Centre, High Road Leytonstone, London, E11 4RE - Tel : 020 8556 7930 - email :