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Hello, I'm Leslie Kerwin, and this is Business Daily from BBC World Service.

When is a diamond, really a diamond?

When it's been formed miles underground a billion years ago,

or when it's been created in a laboratory under temperatures close to the heat of the sun? The answer is both are true. They look and behave exactly the

same, but they are very different in price. The lab ground diamonds are marketed as kinder

to the environment, and they are far cheaper. And that's led to concern about whether the

two kinds have been mixed together with man-made stones passed off as natural.

We're looking at diamonds today that are being recycled, for example, and we're starting to

pick up that there are synthetic diamonds that are also mixed in with the natural diamonds.

In the previous edition of Business Daily, we heard about how the $87 billion

jewelry industry has been shaken up by the mass production of man-made diamonds.

I've been walking around Hat and Garden, London's famous jewellery district,

to ask shoppers if they would be tempted to buy lab-grown diamonds.

Now, what if I said to you, how about a lab-grown diamond?

Never ever appealed to me. I've always wanted natural diamond.

Why?

Because to me, and I know nothing about this so but to me a natural diamond is better than a lab grown diamond and it doesn't feel it wouldn't feel right to have a lab grown one.

Even if it was structurally and looked the same? No.

My engagement is lab grown.

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