I was selling vintage furniture from a market stall in the 1980s when I first came across lava lamps, in an old box. At the time they were really unfashionable, but I loved them.
My then business partner and I approached the inventor, Edward Craven Walker, and asked if we could buy the formula to make our own lamps. He said: 'Why don't you come and take over the business instead?' And that was that.
It wasn't plain sailing, though. Walker hated lawyers, so the deal was quite literally done on the back of an envelope. For years we didn't think he would honour our deal, but three years later the company was ours and we changed the name from Crestworth to Mathmos in 1992.
The world was different then and, being a woman running a manufacturing business, I came up against real prejudice. Our accountants never acknowledged me - they always wrote to my business partner, David. When we'd go to meetings, they'd put the coffee in front of me to pour and then I'd be totally ignored. But retailers were easier to deal with. Now they're all much tougher, even John Lewis. But they need much bigger margins if they're going to survive the internet threat.
We made - and still make - all the lava lamps in a factory in Dorset, where the company has been based since it was founded 50 years ago.
The popularity of the lamps rose through the 1990s and they became the bestselling product in shops' lighting departments. At first, people assumed we had a patent, but we didn't - it had expired a decade before.
Once that was revealed in 1999, we were copied quickly and massively. Cheaper copies came flooding in from China and our sales halved in a year. All the retailers we'd dealt with deserted us. I lost 50% of my turnover in 2000.
Looking back, I didn't act quickly enough. My business partner didn't want to deal with everything so I bought him out. But we should have stuck together. I was juggling a company sale at the same time as restructuring the business and developing new products, which slowed me down.
We haven't managed to regain the lava lamp market and we haven't tried to. Instead, I decided to stick to the top end of the market. I wanted to keep manufacturing the lamps in Britain, which meant I'd never be able to compete with China on price.
We did, however, look to China to create a whole new range of LED lighting products. But even China is getting more expensive. I'm hopeful we'll be able to make everything in England in the future.
Keeping the lava lamps made in Britain has been my best decision. For some periods in the past decade it looked like a mad idea, but I see this as a long game.
Mathmos is privately financed. There has been no outside investment and no bank loans. It's a long-term business. Entrepreneurs are all a bit 'pain in the arse'. We want to do it all our own way.
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