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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The Ultimate Mothers Day Jewellery Gift Guide
With Mothers Day right around the corner, now’s the perfect time to sort out a special gift to show her just how much she means to you. From gorgeous Mothers Day gift sets to simple solitaire necklaces, everyday earrings and so much more - we’re firm believers that jewellery is so much more than just a gift. Discovering a piece of jewellery that’s unique to them show’s thought, care and consideration and when they then go to wear that special piece, they’ll always think of you - which makes it mean that much more. So where to start? Is your mum tricky to buy for? To save you some time we’ve put together a few handy categories we’re sure will fit in with what your mum loves when it comes to jewellery. So let’s discover her perfect present together.
For Mum’s Who Love Sparkle
For diamonds that sparkle just as bright as she does, if your mum loves anything that twinkles in the light, you’ve come to the right place. Handcrafted to perfection, diamonds don’t have to cost the earth and here at Diamonds Factory one of our specialities is providing the best possible jewellery pieces at the best value prices. Whether that be a pair of dazzling diamond earrings or a standout tennis bracelet, you can tailor their jewellery piece to perfection with our various options available like metal, carat, clarity and more.
4 Prong Setting Full Eternity Diamond Ring
From £217
Dual Wall Bezel Set Everyday Bracelet
From £471
Amethyst Cluster Hoop Earrings Charm
From £50
Round Diamond Everyday Delicate Stud Earrings
From £221
4 Prong Setting Tennis Bracelet
From £638
For Mum’s Who Love Effortless Elegance
Does your mum like her jewellery minimal, classic and cool? Jewellery doesn’t have to be complicated, and as a parent there’s nothing more mum’s love than celebrating their children, so why not opt for one of our letter charm necklaces specifically with your initial on. A simple but thoughtful gift they’re sure to love. Everyday bracelets are also a great thoughtful gift for Mothers Day, we offer various styles that are available in various metal types including 14ct gold too.
Love Script Bracelet
From £172
Dual Wall Bezel Set Everyday Bracelet
From £471
V Diamond Initial Pendant Necklace
From £230
S Initial Pendant Necklace in Silver
From £124
Pavé-Set Clover Diamond Chain Bracelet
From £138
For Mum’s Who Love Colour
For the mums who want their jewellery full of punch and personality just like them, we absolutely love colourful jewellery pieces here at Diamonds Factory. We offer a vast array of gemstone jewellery from charming gemstone earrings to gemstone necklaces, bracelets and more. Wondering what gemstone to opt for? What about choosing their birthstone or even yours, so it holds that extra bit of meaning. Not sure what their birthstone is? You can discover more in our helpful guide here.
Oval Ruby Delicate Stud Earrings
From £995
Round Emerald Delicate Chain Lariate Necklace
From £459
Prong Setting Pear Blue Sapphire Pendent
From £77
Amethyst Birthstone Tennis Bracelet
From £396
For Mum’s Who Love Luxury
Is your mum’s motto to go big or go home when it comes to jewels? Who can blame her. Luckily, we’ve got tons of luxurious jewellery pieces on offer that won’t break the bank this Mothers Day. Trending for 2026 and with good reason too, 14ct gold jewellery has seen a massive rise in popularity and screams luxury. Not only that, but it also has fantastic durability and is perfect for everyday wear too.
0.90ct. Full Bezel Setting Round & Pear Diamond Delicate Bracelet
From £607
Prong Setting Dual bar Chain Bracelet
From £134
Toi Et Moi Arched Diamond Stud Earrings
From £1,434
Toi Et Moi Sweetheart Diamond Pendant
From £619
Prong Setting Round Diamond Three Quarter Eternity Ring
From £342
For Mum’s Who Love Matching Jewels
If there’s one thing that always makes for a great gift, it’s a gift set, and ours come gorgeously packaged so all you have to do is find something they’re going to love, add it to basket and let us handcraft and deliver it to your door wrapped to perfection ready to gift on the big day. Most importantly this Mothers Day we’re offering a massive 30% off gift sets from Monday 23rd February 2026 - 30th March 2026 so you can make Mothers Day 2026 one they’re certain to never forget, all whilst being kind to your bank balance too!
Dual Wall Bezel Set Pear Solitaire Pendant, Earring and Bracelet Set
From £94
Round Emerald Floral Delicate Necklace, Earring and Bracelet Set
From £1,317
Cresent Moon Delicate Diamond Chain Pendant and Earring Set
From £94
Four-Petal Milgrain Diamond Chain Necklace and Earring Set
From £177
Pavé-Set Clover Diamond Chain Necklace and Earring Set
From £275