The value of your diamond is determined by four main characteristics - cut, colour, clarity and carat weight as explained below:
| Quality of Cut: | Styles of Cut: |
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| Colour: |
Clarity: |
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| Carat: |
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Current Hallmark Symbols
What is a Hallmark?
Until 1998, a Hallmark consisted of four COMPULSORY MARKS. Since 1998 the date letter has become optional but the other three symbols remain compulsory. The symbols give the following information:
* who made the article
* what is its guaranteed standard of fineness
* the Assay Office at which the article was tested and marked
* the year in which the article was tested and marked
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 AB Sponsor or maker |
 Standard Mark |
 Assay Office Mark |
 2008 |
Sponsor's Mark (formerly known as the Maker's mark)
This shows the person or company responsible for sending the article to the Assay Office. The sponsor may be the manufacturer, retailer, importer, for example.
Standard Marks
These show the standard of fineness - the purity of the precious metal, in parts per thousand.
| e.g |  | The background shape shows the metal (gold).
The figure shows the article consists of 750 parts of gold by weight to 250 parts of other metals - 75% gold. This is equal to 18 carats (18 parts in every 24), the traditional way of describing gold purity. |
| Current Gold Standards: |
 9 Carat |
 14 Carat |
 18 Carat |
 22 Carat |
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| Current Silver Standards: |
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 Sterling |
 Britannia |
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| Current Platform Standards: |
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Assay Office Mark
There are now only four British Assay Offices in existence, but there have been more in the past.
 Birmingham |
 London |
 Sheffield |
 Edinburgh |
Optional Marks
In addition to the Compulsory Marks a sponsor may wish to incorporate any of the traditional marks which have been struck on British articles over the centuries and which have been recognised throughout the world.
Date Letter
This will tell you in which year the article was tested and marked.
Commemorative Marks
Special Marks to commemorate significant national events may also be added if a sponsor chooses. The Millenium Mark to celebrate the year 2000 was very popular and was applied to over 5 million articles of jewellery and silverware. The most recent commemorative mark was to honour the Golden Jubilee of Queen Elizabeth II in 2002.
Other Marks
Other marks have been used historically for example, the Duty Mark and classic marks such as the figure of Britannia to signify Britannia Silver.
This symbol does not appear in all hallmarks, but if it does, it will tell you that the item was marked during a year when duty was levied on gold and silver by the Crown. Duty marks will appear on items marked at the Birmingham Assay Office from 1784 until 1890.
Convention Marks & Other Acceptable Hallmarks
As an alternative to the traditional UK Hallmarks articles may be marked with a Convention Hallmark which may have been applied by any one of the countries included in the International Convention on Hallmarking.
Following a ruling by the European Court of Justice, the UK is required to accept other national hallmarks. Under the guidelines of the British Hallmarking Council.