If I say the word ‘ceramic’, chances are you’d think of something delicate and pretty: blue-and-white china saucers, perhaps, or a vintage flower-sprigged teapot. You wouldn’t necessarily imagine brutal hardness and vicious sharpness. Unless, that is, you have tried one of the new breed of ceramic knives.
For 2,000 years the last word in knife technology has been steel in one form or another, whether old-fashioned carbon steel or the newer stainless-steel composites. The idea of making a knife from ceramic instead seems perverse. For ages I resisted ceramic blades because they look implausible, like toy knives for children.
But when you pick one up and actually use it, there’s nothing childish about the cutting edge. These things are ferocious. They show no mercy on a cucumber or an onion. I’ve been experimenting with a white ceramic Santoku knife (£45) made by Kyocera, the leading Japanese brand. In the evening as I prep the vegetables for supper, I am startled by the ease with which it reduces carrots to thin batons, red pepper to slivers and celery to fine dice. The blade doesn’t look like a real blade, but the evidence is there on the chopping-board.
Roger Morgan-Grenville, who distributes these knives in Britain, says he has found that ‘consumers instinctively don’t believe that something so light’ could handle ‘heavyweight cutting’. At food exhibitions, he does a ‘ripe tomato test’, letting people try to cut as many pieces from a tomato as possible. Ceramic is certainly great for cutting juicy tomatoes into salami-thin slices, and it’s a bonus that – unlike carbon steel, which leaves a nasty rusty taste on lemons and tomatoes – it is as non-corrosive as a pottery mug.
The ceramic used for knives is not the same as china, however. The key ingredient is a rare mineral, mined in Australia, called zircon. After the zircon blade is fired, the ceramic becomes 50 per cent harder than steel. What’s more, it holds a sharp edge about 10 times longer, meaning these knives hardly ever have to be sharpened.
What’s the catch? Read it here.