When jewellers Cobra and Bellamy were robbed twice in quick succession they looked on their misfortune as an opportunity to start designing their own lines. Chris Maume met owners Veronica Manussis and Tania Hunter
Veronica Manussis was on her own and there were five of them. While a couple of them distracted her at the back of the shop, another picked the lock of the display case containing the best gear - the Cartier, the Van Cleef, the Dubuchon. Then, not long after, they did it all over again.

That was ten years ago. But the words "silver" and "lining" were never more appropriate, for the experience of being twice robbed of their top-end jewellery persuaded Manussis and Tania Hunter, the pair behind Cobra and Bellamy, that there had to be another direction.

So, out went the expensive stuff to the auctioneers to finance the new start and Manussis began designing her own line in silver. Just like that. Now in their seventeenth year together, they make an engaging double act - Manussis holding the floor, Hunter all quiet asides and the odd expletive - in their shop off Sloane Square in London.

While Hunter was brought up in the area, Manussis spent the first ten years of her life living in Kenya with her Greek father and half-American, half-English mother. In England since 1962, she did a foundation course at Croydon, although she was most interested in pottery and furniture. She had a shop in the King's Road, Cobra, selling Twenties and Thirties objects and furniture, while Hunter ran a stall, Bellamy, in Kensington Market with two friends, selling Art Deco and Art Nouveau jewellery. The two met through their businesses, although neither can remember quite where, and set up together. Following the robberies and the decision to change tack came commissions from Joseph and soon they were up and running.

Although Manussis does the designing, Hunter's input is vital. "She has the technical knowledge, knows how something is going to hang - she was virtually born with a ring in her mouth," Manussis says. "I say, 'This is wonderful,'" Manussis begins, "and Tania says," - they speak in unison - "'You can't have it.'" Hunter continues: "I look and say, 'No, that's much too expensive, it'll cost a fortune, it's got 15 hinges or something.'" Manussis continues, "Then I'll throw a wobbly and say I don't want to know. But Tania is brilliant because she does know the pricing, and there is a price point to everything, absolutely everything."

There is also Moneypenny, as they call Christine Gordon-Jones, to deal with. She looks after the business side, setting budgets and constructing five-year plans. "I've got to get the whip out occasionally," she says.

The designs exude an elegant simplicity. "Our customers know they can come here and find a very understated, sophisticated look, quite linear," says Manussis. "It's not going to be flashy, it's not going to be everywhere. A Paloma Picasso necklace looks like15 grand round your neck. There's part of me that says, surely not 15 grand for a necklace."

I ask her what she thinks about the pounds 20,000 Armani frock worn by Sly Stallone's bride a couple of months ago. "Obscene, obscene, obscene, obscene," Manussis says, elongating the last syllable like a bohemian Lady Bracknell. Wearability is the nub. "A lot of contemporary work is almost frustrated sculpture," she adds, "though here I am saying that wearing two huge cuffs and a knuckleduster." As well as an Inca feel and shades of sci-fi, the rings and bracelets she is wearing do, indeed, have a fetishistic tang: "Somebody came in the other day, took one look at me and said, 'Who cut the chains?'"

As well as the silver pieces, there are also Cobra and Bellamy watches, their sumptuous collection of costume jewellery, and the Art Deco-influenced work of Barbara Bertagnolli, who sells exclusively through them. "It's important that they're not just selling my work - they enjoy it, too," says Bertagnolli.

Manussis and Hunter also specialise in amber, the fossilised resin of prehistoric trees, which doubled in price after Jurassic Park. "A runner happened to walk into the shop to show me some and I absolutely died," says Manussis. "It was large and it was barbaric, great big chunks of it, and I bought literally everything they had. That is an extraordinary thing - to be the antique that I am and still get passionate and excited about something."

Wanting to set up their own supply, they went out to the Dominican Republic, where much of the world's most beautiful amber is found, with no contacts and not much idea what they were doing. They took a tourist bus to where the mines are. It was the hurricane season. Hunter didn't know that. "I knew, but I didn't tell her," says Manussis. "I wasn't going on my own."

There, they made contact with the miners, who, says Hunter, burrow the equivalent of "half the length of Sloane Street, like rabbits with little pickaxes." They set up a regular supply line, though their original contact is now in jail for an amber-related murder. And now they are both collectors. "I've got an orchid in amber that is 35 million years old," says Manussis. "I've got ants in amber, wasps, a mushroom. This is an obsession."

It's the Cobra and Bellamy success story - from victims of crime to silver surfers and amber gamblers, making their obsessions work for them.

Cobra and Bellamy, 149 Sloane Street, London SW1, 0171 730 2823. Also available from Fenwick, 63 New Bond Street, London W1, 0171 491 4577.