Precious metals are rarely used in their pure form, as they are too soft. Gold, silver, platinum and palladium are generally mixed (alloyed) with copper or other metals to create an alloy that is more suitable to the requirements of the jeweller or silversmith. The hallmark indicates the amount of precious metal in the alloy in parts per thousand (the millesimal fineness). In addition to indicating the town where the item was marked, a unique sponsor’s or maker’s mark identifies the item’s origin and a date letter to represents the year of marking.
All of our products come with a guarantee of the precious metal content through the 700-year-old practice of third party independent hallmarking.
This is a quality control mark placed on gold, silver and platinum and it's a safeguard for purchasers. Basically, the hallmark shows that it has been tested by an independent body (at the Assay Office) and guarantees that the metal is of one the legal standards of fineness (purity).
A hallmark also lets your jeweller quickly check what carat your jewellery is if you have to take it in for repairs or alterations. It is a legal requirement for most articles of precious metal above a certain minimum weight to carry an approved hallmark.
The British hallmark is made up of at least 3 compulsory symbols:
The Sponsor's Mark
This indicates the manufacturer, or sponsor of the item. This consists of the initials of the company who sent in the item for assaying.
The Fineness Mark
This indicates what the metal is and its standard of purity in parts per thousand.
The Assay Office Mark
This identifies the Assay Office at which the item was tested and marked.
The Goldsmiths Hall today
The Goldsmiths’ Company Assay Office in London (also known as Assay Office London or the London Assay Office) is the oldest assay office in the United Kingdom.
The company has provided hallmarking services since the Goldsmiths’ Company was founded in the 1300s.
The company received its royal charter in 1327 and ranks 5th in order of precedence of the 12 Great Livery Companies of the City of London.
The Goldsmiths Hall in 1913
Hallmarking dates back to the 1300s, when Edward I of England passed a law requiring any item made of silver and offered for sale to be at least of equal quality as that of the coin of the realm (silver currency).
The four wardens of the Goldsmiths’ Company were tasked with visiting workshops in the City of London to assay (test) silver articles.
If these articles were found to be below standard they were originally forfeit to the King, but if they passed, each article received the King’s mark of authentication which was the mark of a leopard’s head. By 1478, there were several hundred workshops and merchants manufacturing silver articles in the City of London. It was not possible for the wardens to visit them all, and so the merchants were ordered to bring their items to Goldsmiths’ Hall for testing and marking, with a permanent Assay Office being established in the building.
This is the origin of the term hallmark – struck with the King’s mark at Goldsmiths’ Hall.
In 1544, the Goldsmith’s Company adopted the King’s mark as their town mark, and the mark of the leopard’s head is now internationally recognised as the mark of this assay office.
Metals & Standards
Platinum is a white metal and the most expensive and prestigious option for a ring. It is long wearing and already exceptionally white, so it does not need to be rhodium plated like white gold. Platinum is also used in rings at almost 100% purity. It is a dense metal, so a platinum ring will feel heavier on the hand than other options. Because of its higher cost, platinum is most often used in men's and women's wedding and engagement rings.
Platinum prices - £UKP - 5 / 10 / 15 year spreads
Gold is one of the most common and desired metals used in rings of all varieties. The metal's popularity for men's or women's engagement and wedding rings is unsurpassed. 10, 14 and 18 are the most common carat values found. The larger the carat, the higher the percentage of pure gold in the ring and the more expensive it will be. The hardness and durability of gold varies depending on carat, so it is important to take these factors into account when selecting a gold ring.
Gold rings come in a number of colours, the most common being yellow, white and rose. Yellow gold is the most popular and quintessential colour. White gold is also increasing in popularity but tends to be a bit more expensive than others. When selecting a white gold ring, choosing one that is rhodium plated would be wise. White gold rings are often coated in rhodium to enhance their white colour and protect the gold below from wear and tear. Be aware the Rhodium plating can wear and you may need to have your ring re-plated after a few years wear.
Gold Bullion prices - £UKP - 5 / 10 / 20 year spreads
The Gemological Institute of America, or GIA, is a nonprofit institute dedicated to research and education in the field of gemmology and the jewellery arts.
Founded in 1931, GIA's mission is to protect all buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality. The Institute does so through research, gem identification, diamond grading services and a variety of educational programs.
Through its world-renowned library and subject experts, GIA acts as a resource of gem and jewellery information for the trade, the public and worldwide media outlets.
In 1953, the GIA developed its International Diamond Grading System and the Four Cs (cut, clarity, colour, and carat weight) as a standard to compare and evaluate the quality of diamonds.
Today, the institute is headquartered in Carlsbad, California and operates out of 13 countries, with 11 campuses, 9 laboratories and 4 research centres worldwide.
The GIA set the standard for diamond grading and gemmological identification, and their grading system serves as the international gem and jewellery industry's benchmark credentials.
Shape and Cutting Style: The diamond shape and cutting style.
Measurement: Lists the diamond's dimensions in millimetres.
Carat Weight: The weight of diamond listed to the nearest hundredth of a carat.
Colour Grade: A grading which assesses the absence of colour in a diamond.
Clarity Grade: Clarity grade determined under 10x magnification.
Cut Grade: A grade of cut as determined by a diamond's face-up appearance, design and craftsmanship. A cut grade is available on round diamonds graded after Jan. 1, 2006.
Finish: Grades that represent a diamond's surface and facet placement.
Polish: Rating the overall smoothness of the diamond's surface.
Symmetry: Measuring the shape, alignment and placement of the diamond's facets in relation to one another as well as the evenness of the outline.
Fluorescence: Colour, and strength of colour when diamond is viewed under UV light.
Comments: A description of additional diamond characteristics not already mentioned in the report.
Clarity Plot: A map of the approximate size, type, and position of inclusions as viewed under a microscope.
Proportion Diagram: A map of the diamond's actual proportions.
How do you tell a fake diamond?
Fake diamonds - or what we call diamond simulants- have many different types, they all have the appearance of a diamond, but differ in the physical properties and characteristics from each others, and from diamonds, which is the key to tell which is what. Here's a list of the most popular ones, and how to spot each one of them:
Cubic zirconia (CZ)
This is the most popular one nowadays, it is as brilliant and lusterous as diamond, but with a slightly higher dispersion, and hardness of 8.15 on Mohs scale of mineral hardness. But its Specific gravity (SG) is 5.80, making it heavier than a diamond (SG 3.52) of the same dimensions, so you can differentiate it by weighting it and looking for the weight to dimension table, if it doesn't make sense, it's probably CZ. Usually it has orange pavilion flash. Experienced traders might even recognize it only by holding it.
This is the hardest one to differentiate, and the most convincing one, with a brilliant and fire close to diamond, and a hardness of 9.15 it is the hardest diamond simulant so far. However, it processes light differently, causing doubling images to appear inside when looked at under 10X, that's the best way to spot it.
Low hardness, extreme fire, and has a doubling effect.
Yttrium aluminium garnet (YAG)
Lower hardness & lower fire than diamond, and it also has blue & violet pavilion flash.
Gadolinium gallium garnet (GGG)
Low hardness, and high SG, so much heavier than diamond.
By looking at the facets junctions, they'll be thick, rounded, and far from the sharpness of a diamond's facets junctions, it'll also be easy to scratch and chip, both due to its low rank on Mohs scale of mineral hardness.
Glass & treated glass
Much lower brilliance, lustre and hardness (visible in facets junctions), and a see-through effect.
Low hardness, extreme fire.
Now there's a whole other category which is the Synthetic diamond. This is not a fake diamond, but man-made in a laboratory. None of the methods above can detect it whatsoever. A look under the microscope may or may not detect it, depending on its type (HPHT or CVD), and depending on the quality. Only very advanced equipment from De Beers can detect them. Its another good reason to insist on certified stones.