Friday, October 28, 2016

Natural pearls are exceptionally rare

Pinctada maxima pearls are the ones branded internationally as South Sea Pearls, and about 80 per cent of the world’s Pinctada maximas are found off the Australian coast. Where other oysters can produce pearls up to about 8 millimetres in diameter – maybe 10mm at a push – in Australia this is the bare minimum benchmark. The pearling companies along the remote north-western coast have long plumped for quality over quantity. And that’s how the Willie Creek showroom ends up nonchalantly displaying a pearl necklace valued at $100,000 (Dh282,500).



It’s not just about size, though. Four other key characteristics come into play – colour (the whiter, the better); surface (fewer bobbles and markings); lustre (shiny is good); and roundness (if it rolls smoothly like a marble, then it’s a winner).


The guide produces what she calls a "whale pearl". It’s 18mm in diameter, and would be valued at between $30,000 and $40,000 (up to Dh113,000), but for a few surface imperfections and a slightly off-round shape. That takes the price tag down to a mere $8,000 (22,600).

The oyster shells get bigger as they grow older – some grow to dinner-plate size – and the bigger the shell, the bigger the pearl that is likely to grow in it.

Natural pearls are exceptionally rare – they’re found in every 10,000 to 100,000 shells depending on whom you ask – so the vast bulk of the world’s shell production is done by cultivation. This involves artificially inserting an irritant into the oyster’s gonad – Mississippi mussel shell is used at Willie Creek because it is five times more dense than Pinctada maxima shell and thus shows up under X-ray.

The oyster then tries to soothe the irritation by producing nacre – better known as mother-of-pearl. It’s not too dissimilar a process to the way humans produce tears to fight irritants in the eye, but the nacre builds and solidifies over time around the irritant.

Here again, the tides come into play. They repeatedly flip the oyster shells, meaning the build-up of nacre is consistent on all sides to give it a more spherical shape. But it’s a two-year process, and the first pearls produced by the younger oysters are at the smaller end of the scale.

http://www.thenational.ae/arts-life/ultratravel/chasing-south-sea-pearls-in-broome-australia