‘The finest gemstones in the world are in British houses’: family jeweller Pragnell makes the move to Mayfair

Should the Duke of Cambridge be looking for a present to mark the arrival of the new prince, he could do worse than popping along to Pragnell Fine Jewellery on Mount Street, where among the displays of new and vintage jewellery is a particularly special 1920s sapphire ring.

It features a 4.2-carat, velvety blue square stone, mined in the late 19th century from the famed Kashmir sapphire mines in the Himalayas - a source whose supply ran out in 1887.

“It’s incredibly, incredibly rare,” says the ever-ebullient managing director Charlie Pragnell, grandson of George Pragnell, who established the house under his name in 1954. “To find a stone of that size from a mine that finished over 100 years ago is really quite remarkable. It might be the only square Kashmir sapphire in existence.”

Rare stones like this are something of a specialty for Pragnell, which began life as a small family jeweller in Stratford-upon-Avon, where it is still headquartered.

The two-storey store on Mount Street, which opened late last year, is its first shop front in London, although, says Charlie, “we’ve always had a link with London. We acquired Philip Antrobus, the Bond Street jeweller who made the Queen’s engagement ring; my mother’s family owned Waters & Blott, which was one of the largest jewellery manufacturers in London since the 19th century; and we’ve had a by-appointment office in London for years.”

This store, though is a huge step. “It felt like the right time to bring something to Mayfair that wasn’t being offered: rare jewels, handcrafted in Great Britain.”

The rarity includes the ever-changing selection of vintage jewels - from Victorian old-cut diamond rings and that Kashmir sapphire to signed Cartier Art Deco bracelets and 1950s pieces by Van Cleef & Arpels - alongside Pragnell’s ‘Masterpieces’, designed around exceptional gemstones and handmade in the house’s British workshops.

Some of these feature new stones: Charlie shows me a pair of emerald-cut Fancy Vivid yellow diamond earrings totalling seven carats, cut from a South African stone specifically for Pragnell. “It’s very rare to get Vivid emerald-cuts; there is no other set like that in the world,” he says.

Other pieces are showcases for old, ‘important’ stones: an unheated Burmese ruby, an eight-carat old-mine cut Colombian emerald, a D-flawless pear-shaped diamond from the historica Golconda mine.

The Pragnell family sources these gems from private clients and auctions; many of them have been in the same family for generations. “The very best stones come from mines that were exhausted in the old world, and those mines belonged to the British,” says Charlie.

“I still believe that the vast majority of the finest gemstones in the world are in British private houses, but they’re buried in a safe. And when someone inherits a big bag of jewellery and wants to turn it into a yacht, or a flat in London perhaps, they come to us.”

He’s particularly excited about the latest Masterpiece to emerge from the workshop: a 3.83-carat Brazilian Paraiba tourmaline set in a piece of carved quartz, its electric hue enhanced by a deco-style border of diamonds and enamel. “It’s an extraordinary stone: a gem collector’s gem. We honestly don’t know what to ask for it because it’s the only one like it.”

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But not everything in store is ‘price on application’. “We haven’t changed our prices because we’ve come to Mayfair,” Charlie points out. Pragnell’s in-house, contemporary fine jewellery collections include feminine floral designs, delicate, everyday diamond pieces and the youthful Rockstar range, with prices starting in the hundreds.

And its antique and period offering, which accounts for three-quarters of sales in London, provides quite remarkable value for money, along with a sense of assurance about what you’re buying that can only come from an old-school family jeweller. Good news for a push-present seeking royal, and the rest of us.

14 Mount Street, Mayfair, London W1K 2RF; pragnell.co.uk