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)
Where Hallmarking Began
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.
Today
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.
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We can’t get enough of the latest looks from the Oscars 2026 and it comes to no surprise when it’s the one monumental night a year when all the hottest celebrities get together to celebrate all things film. Not only that, but it’s also where lavish and glamorous looks meet on the red carpet styled with the most eye-catching jewellery pieces to match. Statement necklaces certainly took centre stage, alongside the most amazing earrings, jaw-droppingly sparkly diamond rings and so much more. From the one and only Kylie Jenner to film royalty Anne Hathway, Priyanka Chopra, Kate Hudson and so many more incredible names, let’s take a look at the looks we loved from the Oscars 2026.
Infinity linked Tennis Necklace
From £7,194
Hidden Halo Diamond Solitaire Pendant
From £305
Infinity linked Tennis Necklace
From £6,296
Semi Bezel Setting Classic Moissanite Solitaire Pendant
From £475
Semi Bezel Setting Round Diamond Journey Pendant
From £307
Bar Setting Round Diamond Journey Pendant
From £264
Prong Setting Moissanite Solitaire Pendant
From £290
2 Prong Setting Round Diamond Journey Pendant
From £236
Prong Setting Round Diamond Tennis Necklace
From £1,942
Anne Hathaway in Bvlgari
If there’s one thing Anne Hathaway didn’t shy away from at this year’s Oscars - it’s diamonds, and if there’s one night when you can go full glitz and glamour, then this was certainly the occasion for it. Featuring a decadent array of Bvlgari diamonds, Anne sported the most mesmerising beautiful pair of drop earrings with an out-of-this world diamond necklace to match, weighing in at a massive 35 carats, with rumour that it took over 800 hours to create too - if there’s only thing we’ve learnt over the years, it’s that nothing is too much for the Oscars. Diamonds really are a girl's best friend.
@20thcenturystudios via Instagram.com
Kylie Jenner in Lorraine Schwartz
One thing we love about Kylie Jenner is that if Timothy Chalemet has a big event coming up, she’ll certainly be attending it with him - and if she’s attending, she’ll be doing it in style. Decked out in nearly 200 carats worth of diamonds and paired with a sparkling sensation ruby red no Schiaparelli dress, Kylie really stepped above and beyond for this year's Oscars.
@kyliejenner via Instagram.com
Priyanka Chopra in Bvlgari
Priyanka Chopra is an icon in her own right and she showed it all off with her effortlessly elegant look at this year’s Oscars. Wearing the most eye-catching 14-carat cushion-cut sapphire necklace and paired with a diamond ring and some more subtle diamond stud earrings too, if there’s one thing about this woman it’s that she’s bringing the glamour wherever she goes, especially when it comes to jewellery.
@priyankachopra via Instagram.com
Kate Hudson in Garatti
Nominated for best actress, Kate Hudson is known for being anything but subtle with her sparkle, and with a showstopping dress like that it was only right she wore an array of the most incredible diamonds to complement it. Featuring 41 carats of gorgeous green diamonds from Garatti, our diamond experts say this necklace comes in at around an eye-watering 35 million dollars - because if you can’t at the Oscars, then when can you?
@katehudson / @charlottetilbury via Instagram.com
Our Expert Jewellery Predictions for 2026
The move towards bigger, more noticeable jewellery is something we expect to see a lot more of through 2026. Red-carpet moments like the Oscars tend to set the tone for what people start looking for, and this year the message was pretty clear — jewellery is becoming the main event again rather than just something subtle in the background. We’re already seeing more interest in larger centre stones, statement necklaces and bold diamond earrings, particularly for weddings, milestone celebrations and special occasions where people want a piece that really stands out.
Shop Our Favourite Statement Necklaces
Got an occasion coming up and thinking about investing in your own statement necklace? With showstopping statement necklaces being all the rage at this year’s Oscars, here’s a few of our favourites so you can get the look for less at Diamonds Factory.
Infinity linked Tennis Necklace
From £7,194
Hidden Halo Diamond Solitaire Pendant
From £305
Infinity linked Tennis Necklace
From £6,296
Semi Bezel Setting Classic Moissanite Solitaire Pendant
From £475
Semi Bezel Setting Round Diamond Journey Pendant
From £307
Bar Setting Round Diamond Journey Pendant
From £264
Prong Setting Moissanite Solitaire Pendant
From £290
2 Prong Setting Round Diamond Journey Pendant
From £236
Prong Setting Round Diamond Tennis Necklace
From £1,942