It takes a long time for broken bottles in the sea to metamorphose into seaglass. It takes even longer for them to reach the jewellery department at Liberty.
Bank holiday weather permitting, thousands of people will today wander along beaches, sedately hunting for natural treasures. Gina Cowen was doing the same thing 18 months ago in South Africa, when she spied what looked like blue and white jewels shining in the sand.

It was seaglass - broken glass battered by the elements into translucent pebbles. She collected a handful. "I wanted to drill them and string them into a necklace," she says. "I thought it would be like having a ring of solid water around your neck."

This week a display of these necklaces, which fetch up to pounds 250 each, can be found at Liberty in central London, as well as at a selection of stores across the West End.

With their organic, clean shape, environmental credentials (they are, after all, recycled) and obvious wearability, she has unwittingly tapped into the zeitgeist of the 90s and can reasonably expect to reap the profits.

It's the kind of rise to success guaranteed to instil envy in craftsmen across the country. But it is has been an unlikely one, punctuated by discouragement and rejection from the jewellery and craft establishment, and one that has forced her to confront issues of commitment and dilettantism that affect a whole generation.

At 38 and single, with a career that had spanned "picking up fag ends and feeding the tortoise" at the Chelsea Arts Club through editing anthropological essays in Africa to managing classical musicians, Gina decided to risk focusing on jewellery. Having already studied jewellery- making at night school, on her return to Britain she attempted to investigate how she could turn the seaglass into necklaces.

She may have been enthusiastic, but the jewellery establishment, she said, could not have been less interested. Her "jewels" were made of broken bottles - hardly worth the time of people used to dealing in carats. One head of technology who she consulted went so far as to tell her her idea was ridiculous. ("Nobody's interested in beads any more," he said.)Despite Gina's assertion that these are not beads, he spent two hours telling her what a ridiculous idea it was. "It felt like there was this inherent distrust of innovation," she said.

Undaunted by the rebuffal, she persisted until she found Holt, a gemstone shop in Hatton Garden, where staff showed her the best equipment and where to find it. After three more months practising and researching different drills, she began to turn the battered glass into jewellery. "I didn't really know if there was a market for them or not. But I just wanted to make them because they were beautiful," Gina says.

But no one is immune to material concerns, and she was pleased to find she had been shortlisted for a setting-up grant from the Crafts Council. ("I was still making the jewellery on my bedroom floor".) At the interview, she said, she was met by a panel of six people. The first thing one of them said was: "I see from your CV that you've had a rather chequered career." "I could feel by their attitude straight away that I wasn't going to get it," she says.

Disappointed, as she had hoped to get funds to start a studio, and frustrated by the fact that the establishment apparently felt that what she was trying to do was "unacceptable", she went out to cheer herself up. When she got home, however, there was a surprise on her answerphone. "There was a message from Liberty saying they'd like to see my work and from Egg saying they'd like to show it in their shop. Jess James had already shown interest."

Gina is the first person to admit that she has been lucky. But she ascribes that luck to her belief in what she was doing and her determination. It only worked, she says, when for the first time she was able to mentally commit to one thing.

Her dilemma, she believes, is one common to many children of the post- war generations - a paralysis caused by choice. "All my life I've been interested in and unfortunately good at many things, so I could never decide which one thing I wanted to do," she says.

Part of the problem, she believes, is the pressure to be an achiever from an early age. Her CV is testament to this, listing a Cambridge degree in English, fluency in French, German and Italian, Piano and Violin to Grade 8 and professional singing as well as painting, sculpture and weaving.

In the early 80s, she decided she wanted to be a singer and trained privately for four years. While working part-time at the Chelsea Arts Club, she says, it was jazz musician George Melly who made her realise that her aims were unrealistic.

"I was talking to him and told him I wanted to be a singer. He said: 'So why aren't you singing now?'" She needed to earn money to survive, she replied. "And he told me that unless I would die if I couldn't sing then I shouldn't do it. It really struck me ... he was absolutely right," she says.

"I've worked with people who are at the top of their careers and I felt that my life was somehow a failure if I couldn't be brilliant at one thing," she says. "But I couldn't find that one thing and it left me in a state of depression."

Then at the beginning of last year she rediscovered a quote from Goethe in her diary. "Until one is committed, there is hesitancy. The chance to draw back, always ineffectiveness concerning all acts of initiative (and creation)," it read. "There is one elementary truth, the ignorance of which kills countless ideas and splendid plans, that the moment one definitely commits oneself, then providence moves too ..."

It was this that inspired her to commit to her jewellery. "I just decided to see where it led me, without any sense that I would make money," she says. "I could have gone back and taken a full-time job, I could have gone back to the music business at which I was quite successful ... I had no idea if I was doing the right thing. It was a leap of faith," she says.

But focusing on one thing gave her peace of mind. And she believes it was this final decision to commit to her jewellery that gave her the courage to pursue her craft.

For now, "on the crest of a little wave", she spends her time searching the world's beaches for glass - Majorca, for instance, has some wonderful colours, she says.

One disadvantage of producing something so quintessentially Nineties is that it is hard to see how it can develop. But the past 18 months have made Gina more relaxed about that, too.

Her eyes have been opened, she says, to the fact that it's not a failure to do many things and keep moving on. In a modern workplace, where one might be lucky to stay in the same job for five, let alone 50 years, serial commitment, she says, is the key.

"I may not even be doing this in two years' time," she says. "You see, there's a really great film that I want to make..."