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We’ve teamed up with Klarna to provide flexible payment options, allowing you to shop the way you want. With Klarna, you can split your payment into 3 instalments or choose to pay later, making your shopping experience smoother and more convenient. Your order total must be between £100 and £499 to qualify.
We’ve teamed up with Klarna to provide flexible payment options, allowing you to shop the way you want. With Klarna, you can split your payment into 3 instalments or choose to pay later, making your shopping experience smoother and more convenient. Your order total must be between £100 and £499 to qualify.
March 16, 2026 | by Emma
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It is law within the UK that every item of precious metal sold such as Platinum, Gold, Silver is stamped labelling the item with the type of metal it is. Platinum pieces which weigh less than 0.5 grams, 18ct Gold and Palladium pieces weighing less than 1.0 gram and Silver pieces weighing less than 7.78 grams are except from hallmark.
At Diamonds Factory all our products are hallmarked as per UK hallmarking law from London Assay Office (The GoldSmith Company)
The Goldsmiths' Company Assay Office is the oldest assay office in the United Kingdom. It 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.
Hallmarking dates back to the 1300s when Edward I of England passed a law requiring any item made of silver, which was offered for sale, to be at least of equal quality as that of the coin of the realm (silver currency). The 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 destroyed and the metal forfeited to the King. If they passed, each article received the King's mark of authentication - 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 so the merchants were ordered to bring their items to Goldsmiths' Hall for testing and marking and a permanent Assay Office was 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.
The Goldsmiths's Company Assay Office is still based at Goldsmiths's Hall and remains the oldest company in Britain to be continually trading from the same site. However, it also has two satellite offices; at Greville Street in Hatton Garden in the heart of the London jewellery quarter and within a high security complex near London's Heathrow airport. It now has a new off-site facility within the Dalston-based jewellery manufacturer, Allied Gold. This is the first time in the Assay Office's 700 year history that it has opened permanent hallmarking services on a customer's premises.
In addition to hallmarking, the office has now expanded its range of services to support the jewellery trade and enforcement authorities. It offers a variety of specialist analytical services including nickel, lead & cadmium testing, antique silver dating, non-destructive compositional analysis, plating thickness measurement and a melt and assay service for scrap precious metal carried out in their fully independent on-site laboratory. Other services offered are a jewellery valuation service, laser marking, trading standards assistance, high quality photography and a comprehensive range of training and educational seminars, lectures and specialist events.
The Allure of Yellow Diamonds
Sure to make a statement, yellow diamonds are rising in popularity and it comes to no surprise just by looking at them with their gorgeously bright and enchanting hues. We’re noticing more and more that customers are preferring their jewellery to be far less about following a crowd, and much more about individuality - and yellow diamonds certainly provide exactly that. With 0.001% of the total carats mined featuring yellow diamonds, their rarity makes them even more unique and valuable, making them a fantastic choice for jewellery.
Yellow Diamond Circle Designer Pendant
From £2,687
Yellow Diamond Classic Half Eternity Ring
From £1,356
Yellow Diamond Cluster Earrings
From £1,334
Yellow Diamond Cross Pendant
From £24,823
Yellow Diamond Designer halo Earring
From £4,142
Yellow Diamond Designer Earring
From £91,480
Yellow Diamond Designer Earring
From £37,752
Yellow Diamond Designer Pendant
From £16,567
So What are Yellow Diamonds?
Yellow diamonds are a natural, fancy coloured diamond that’s created when nitrogen enters the diamond's crystal structure. The more nitrogen involved, the deeper and more intense yellow the diamond will be. First discovered in 1867 in South Africa, today, they can be found all over the world.
Are Yellow Diamond Engagement Rings Popular?
Yes! Yellow diamond engagement rings are becoming an increasingly popular choice as an alternative to traditional diamond rings. In the past year alone, customers are searching for yellow diamond engagement rings over 40% more. Adding colour into an engagement ring can feel like a daunting task, which is why we find customers often like to opt for something where different metals and diamonds are mixed like a trilogy ring.
The Colour of Summer
Step aside traditional white diamonds because warm and dazzling butter yellow diamonds are set to steal the show this summer. Evoking radiance and charm and matching the warmth of the sun, it comes to no surprise as to why yellow diamonds are known and loved most for evoking pure joy. From yellow diamond engagement rings to a gorgeous pair of yellow diamond earrings, if you’re looking to update your jewellery collection for Summer 26’, yellow diamonds really are the way to go.
Audrey Hepburn and the Tiffany Yellow Diamond
When we look back at iconic yellow diamond jewellery pieces through the years, our minds are instantly transported to Audrey Hepburn wearing the iconic 128.54-carat Tiffany yellow diamond necklace. With 82 precisely cut facets, this absolutely spectacular piece was worn specifically for the Breakfast at Tiffany’s promotional photos in 1961 and is one of the largest yellow diamonds ever discovered. Set in Jean Schlumberger’s Ribbon Rosette Necklace, you simply can’t think about yellow diamonds without honouring this worldly piece.
Celebrities Seen in Yellow Diamonds
Lady Gaga - Seen wearing the iconic Tiffany diamond that was reset in 2012 at the 2019 Oscars, she was actually the third person ever to wear that treasured stone.
Victoria Beckham - If there’s one thing Victoria Beckham is known for, it’s her never-ending collection of jewels. In 2006 she was seen sporting an estimated 2.5m emerald cut yellow diamond ring, and in 2018 the yellow diamond collection grew as she sported a vivid, canary yellow square cut yellow diamond ring.
Jennifer Lopez - We can’t mention celebrities and yellow diamonds without paying homage to J Lo’s exquisite 30-carat yellow diamond ring from her ex-husband Marc Anthony.
Kelly Clarkson - Another showstopping yellow diamond engagement ring, Kelly Clarkson rock features a massive 5 carat canary yellow diamond as the centrepiece.