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Hallmarks and Precious Metals



Precious Metals Comparison Chart


What is a Hallmark?

A hallmark is a very important detail that should be present in each piece of jewellery purchased. This is mark of assurance, and provides a clear indication of the quality of metal, having been tested at one of the country's Assay Offices. Each stamp carries a particular mark, an explanation of which we have included below. 


Comparing Precious Metals by Weight

For converting the weight of one metal to another. This is especially handy to gain a better understanding of equivalent weight and for estimating how heavy one ring will be in an alternative precious metal choice. We have provided an example of how such a chart works, and have attempted to cover most of the typical metals.

You will see from this chart that despite similar appearances, most metals vary in their respective weight. The basic cost of most metal is calculated by the weight, against the daily fixed metal price giving the basic cost. Other considerations for the final price of any jewellery item include any fashion price, manufacturer / retailer markup, stone costs, labour charges, tax, duty and shipping.

Click here to view our precious metal weight conversion chart


Where is Gold Hallmarked?

The tests are carried out by an assay office, of which there are four in the UK , London , Birmingham , Sheffield and Edinburgh. These are the symbols represented in the hallmarks for the relevant assay office in the UK. Each of the Assay Offices of Great Britain receive an astounding quantity of items, with the largest, the Birmingham Assay Office, working through over 12 million items per year.


Brief Explanation on Precious Metal Marks



9 Carat Gold

9ct Gold is available in a few colours, most popularly yellow and white gold. This is a less expensive precious metal than 18 carat gold. It contains 37.5% gold and is alloyed with other metals to increase the hardness, durability and colour. It is represented by the figures 375 in hallmarks. Not as hardwearing as 18 carat gold or platinum, jewellery in 9 carat gold can feel lighter when worn, but remains very popular and is widely used in jewellery production. 9ct white gold hallmarks and 9ct yellow gold hallmarks will carry this figure. 9ct Gold tends to have a hardness level of 120 Vickers.


14ct Gold 

14ct Gold is most generally represented by the 585 symbol within the hallmark. This is an alloy of Gold that is between 9ct and 14ct Gold. The symbol represents the fineness of the Gold which is 58.5% pure Gold. This is often seen abbreviated to either 14ct, 14kt or 14K. 14ct Gold jewellery is very populare in the USA than the UK, where 9ct Gold and 18ct Gold tend to be more readily available.


18ct Gold

This is one of the most popular precious metals for engagement rings and high quality jewellery. It contains 75% pure gold and is represented by the figure 750 on hallmarks. It is available in both yellow and white gold. Because of the high content of gold, 18 carat white gold would naturally appear more of a straw white colour. It is for this reason that white gold jewellery sold is Rhodium plated to finish the item with a very white, hard and durable coat. This hard finish will, over a long period, eventually wear, especially on rings worn on a daily basis. 18ct Gold tends to have a hardness of 125 Vickers.



Recently popularised by the granting of a legitimate hallmark, Palladium has steadily risen as a metal of choice, possessing many of the characteristics of Platinum, but at a much lower price point. Further information on Palladium can be found in our Palladium Metal section of the website.

Click here for more information on Palladium



Most platinum sold in the UK is 95% pure. It will thus have hallmarks with the figures 950, denoting the purity and may bear another quality mark, the Orb.


A Little More About Platinum

Platinum is naturally a hypoallergenic metal and always remains white. Scratches and wear will only displace the precious metal, making it extremely hard wearing and durable. Scratches and wear will produce a natural even finish to the ring. To bring it back to 'as new' condition, it will merely need to be repolished. A good idea is to have this done at the same time as buying your wedding rings so that both engagement ring and wedding rings are pristine for your wedding day. For more information on platinum as a choice for your jewellery, please visit A ring in platinum will be approximately 40% heavier than the equivalent ring in 18ct gold. Due to its hardness platinum will always provide excellent protection for a diamond. Platinum settings provide the best security for a diamond. Platinum will also retain the natural white colouration, making it an ideal choice. However the weight of Platinum and the subsequent cost can mean that consideration and budgeting is required for any engaged couple considering Platinum wedding rings as their first choice.


Rosebud Platinum Ring   Platinum Diamond Earrings   Platinum Diamond Ring   Platinum Diamond Pendants
Rosebud Platinum Ring   Platinum Diamond Earrings   Platinum "Infinity" Ring   Platinum Diamond Pendants

Naturally white in colour this is the finest precious metal used in jewellery. It is more expensive than gold due mainly to its rarity. Mining platinum involves extracting ore from 2000 metres below the surface of the Earth. Platinum is embedded in small particles of this ore so it takes over 10 tonnes of ore to produce a single ounce of platinum.


Choosing the Right Metal

The following questions are regularly asked by clients trying to decide which metal is best.

So which precious metal do I choose?

This is a matter of personal choice but a few factors may help you decide which you will want to purchase. Firstly budget will be a deciding factor. If you are looking for white gold jewellery, platinum is naturally white, but 18 carat gold will be perfectly adequate and will have a very high polish and ultra white rhodium finish, furthermore it might be a more affordable option.

But most of my jewellery is yellow gold. Which should I choose?

If you already have one colour of gold in your wardrobe, you may wish to remain with one colour, or buy jewellery that combines white with yellow gold, thereby introducing white into your collection. If you are interested in any of our jewellery and cannot see your preferred combination, we can tailor make the piece for you if you contact us.

Should I buy platinum if my other jewellery is gold?

There is no reason why you shouldn’t. Platinum is a luxurious metal that is very pure and will always retain its natural whiteness. It will blend in with jewellery that is white gold and will compliment other jewellery that is yellow gold, only adding versatility to an existing wardrobe.

Should I worry about rhodium plating wearing away?

The rhodium plating applied to white gold jewellery is extremely hard and will take an enormous amount of wear. The colour will remain and it would take a long time to notice any change in colour. When your jewellery needs re-polishing, this can easily be done by a jeweller and the piece can be re-rhodium plated to bring your ring back to the original condition. We would be happy to provide this service at any time. Rhodium plating will not affect hallmarks and is a applied to white gold jewellery by most jewellers.

One of the newest metals that has become more available is Palladium. It is now very easy to produce palladium jewellery, including wedding rings and engagement rings. Further details of the advantages of this metal can be found on our Palladium information page.