This Japanese tour promised me a pearl, but there was one catch I hadn't expected

I had never given any thought to oysters. I don't eat shellfish and I don't wear pearls, so they were entirely divorced from my world - like french polishing or ballroom dancing. Then I visited Iseshima in Mie Prefecture, on Honshu Island, Japan, and suddenly the world was my oyster. Or something.

I spent a lovely sunny morning at the Pearl Farm Experience at Pearl Miki (pictured), where laddered pearl-farming rafts stretch out across the still waters of Ago Bay.

I knew that oysters in Japan were traditionally harvested by freediving women, known as Ama, who plunge to the seabed without oxygen tanks while wearing white cotton outfits that make them look like aquatic windsocks.

As a guest I was not expected to freedive, only to choose and shuck a pre-dived oyster. I selected an oyster from the tray presented to me, and struggled to prise open the shell. I was told to hold the shell in the centre with my thumb, insert a knife into its mouth and turn the blade 90 degrees clockwise.

"When you open the shell, you may find a pearl with your knife," said the farmer, Yoshiko Yamaoka. "But be careful not to scratch it."

I was told that it was down to luck whether my oyster is nursing a pearl. "It's already opening its mouth," said Yamaoka, "but it's not so healthy. So you'd better try another."

I knew it. However, my second oyster contained a pearl. I bathed my pearl in saltwater to remove the sticky paste around it, and was then told to massage the pearl about 10 times. I felt like, um, a pearl-clutcher.

My favourite part of the experience was the opportunity to feed oyster meat to the fish that gather beneath the rungs of the pearl rafts waiting for food drops.

Scores of smaller fish darted around angry-looking blowfish, and beat them to almost every morsel I dropped. The fish fight was a comic but uplifting spectacle, as if the little guy might really have a chance to beat the bullies.

The next stage of the Pearl Farm Experience was to pass my pearl to an expert at the pearl-farm jewellery workshop to assess whether it was marketable.

The writer was a guest of the Kii Peninsula