It all began when the world’s largest cache of Pinctada Maxima oysters was discovered on the seabeds off the northwest coast of Australia in the late 1870s. These oysters’ claim to fame is that they yield the largest and most voluptuous of pearls, which today we call South Sea pearls.

In its heyday, Broome was the base for some 400 pearling luggers and 3,500 divers, and supplied about 75 per cent of the world’s mother of pearl shells.

The arrival of the plastic button and the depletion of the natural beds saw the decimation of the industry, but it’s still a good place to buy South Sea pearls, thanks to enterprising pearlers who learned to do for the Pinctada Maxima oyster what the Japanese had done so successfully with the akoya oyster – namely, develop a method of producing cultured pearls of a quality and beauty that almost matched natural pearls, which were becoming harder and harder to find.

South Sea pearls offer a lot of bang for your buck. Accurate comparisons are hard to make, but you could easily save up to £2,000 on a necklace that would cost £9,000 in the UK. They have an average diameter of 12-14mm, occasionally going up to 20mm, compared with less than 8mm for the Japanese akoya cultured pearl. Their coating of nacre is also infinitely thicker, with a greater lustre to it.

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Chinatown in Broome is awash with sellers of pearls, almost all offering a wide variety – not just South Sea ones. There are two sources that come with some provenance behind them. One is Paspaley Pearls (2 Short Street). This is probably Australia’s best-known pearling family, and today has over 20 farms, stretching more than 1,550 miles across the pristine waters off the northwest coast of Australia.

The headquarters are in Darwin, but the Paspaley presence in Broome looms large. In its shop in old Chinatown, you’ll see as wide a selection of pearls of every kind as most of us could probably take in. There are all sorts of fancy pieces, some very beautiful, but I think it’s best to choose a classic string.

Bob Reed, of Linneys (25 Dampier Terrace, Chinatown), is another fine source of pearls. It’s from him that I bought my own string of slightly grey-tinged South Sea pearls. I went determined to come away with a classic double string of medium-sized pearls, but it soon became clear to me, my companions and Bob Reed that the grey-tinged irregularly-shaped South Sea ones suited me best. The lesson I take from this is that you should take time to try on many different strings.

There are five qualities to bear in mind: lustre, size, shape, surface and colour. As to prices, again it is difficult to make comparisons, since it takes an expert eye to spot the differences in quality. But my impression (gleaned from valuations by experts) is that the pearls I bought there cost me a good deal less than they would have done back in Blighty.

Johannesburg for diamonds

Johannesburg sounds as if it’s just the place to hunt for diamonds. After all, ever since the first South African diamond was found near the Orange River in 1867, it’s been one of the biggest sources of those precious little lumps of pure carbon that we’ve all learned to call diamonds (it comes from adamas, the ancient Greek word for invincible).

By a combination of clever marketing and their inherently sparkly nature, they’ve been skilfully transformed into the world’s biggest symbol of passionate love. So the buying of them should ideally involve a little romance, in which story and provenance have a role to play.

However, if it’s a bargain you’re after, the sad truth is that it scarcely matters where you buy your diamond (though one dealer I spoke to did mutter that Bahrain, which has no sales tax, is a pretty good bet). Diamonds operate in a global market, universally quoted in dollars, and carat for carat, quality for quality, the price varies little around the world.

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