THE SECRET LIFE OF GEMSTONES

WHILE GEMSTONES ARE CERTAINLY FASCINATING, THERE IS MORE THAN MEETS THE EYE WHEN IT COMES TO THEIR UNIQUENESS. HERE ARE SOME INTRIGUING THINGS YOU DIDN’T KNOW ABOUT THEM, BUT SHOULD. YANNI TAN BREAKS IT DOWN

There is more than meets the eye when it comes to the uniqueness of gemstones. Discover their secrets here

1 THERE IS A NEW CATEGORY OF DIAMONDS: THE CHAMELEON

So you know all about coloured diamonds and colour-change gems. How about an extremely rare type of colour-change diamonds, called chameleon diamonds? According to Tay Kunming, director of Far East Gems & Jewellery and a local diamond specialist, a chameleon was first discovered at the Gemological Institute of America (GIA) in the early 1950s. These chameleon diamonds react to heat and light by changing their colour from green to yellow. This unusual phenomenon still continues to baffle scientists, reports Kunming.

2 THERE ARE ALIEN GEMSTONES

Moldavite, a translucent green extra-terrestrial gemstone rarer than rubies or emeralds, is thought to have been formed during a meteorite impact in southern Germany some 15 million years ago. Also very uncommon and sought-after by collectors are meteoric versions of peridot, an olive-green gemstone found on earth, which comes embedded in stony-iron meteorites called pallasites.

3 GEMSTONE COLOURS CAN FADE

Some gemstones are especially vulnerable to light—not just sunlight but strong artificial light. Kunzite is a pink to lavender type of spodumene that can lose its colour even with a few hours’ exposure to direct sunlight. Other gemstones whose colours could fade include aquamarines, aventurines, chrysoprase, corals and brown topaz. In general, it is advisable to store any gemstone in a dark place and minimise its exposure to bright light.

4 SOME GEMSTONES ARE RADIOACTIVE

Irradiation is a common treatment used to change or improve the colour of certain gemstones, but some littleknown gemstones are naturally radioactive. Two attractive and commercially popular examples are the aqua-green amazonite and the bright purple sugilite, which are only barely radioactive and do not pose any health hazards.

5 THERE IS A PLANET MADE OF DIAMONDS

A “diamond planet”, named 55 Cancri e, has been discovered. In 2010, astronomers had hypothesised that the planet’s graphite surface was embedded with a thick layer of diamond. Three years ago, another study suggested that the carbon-to-oxygen ratio on the planet was not as high as previously thought, and the planet was more “a diamond in the rough”.

6 THE BLACK PRINCE’S RUBY IS ACTUALLY A SPINEL

The red spinel was known as the Balas Ruby during medieval times, with the name Balas deriving from a province in northern Afghanistan called Badakhshan. And because the Badakhshan mines were the source of many of the finest early red spinels, they were thought to be one and the same. The 170-carat crimson Black Prince’s Ruby on England’s Imperial State Crown was discovered to be a spinel in modern times.

7 EVEN THE VIKINGS USED GEMSTONES

Like polarised sunglasses, the violet-blue iolite has the same capability to block the glare of sunlight reflected off surfaces such as water and objects. The Vikings were known to carry the gemstone with them and use it as a “looking glass” lens to find the sun on a cloudy day, which would have poor visibility caused by diffused sunlight and glare from the sea surface.

8 THE STAR EFFECT IS EXHIBITED IN MORE THAN JUST SAPPHIRES

Everyone knows how beautiful star sapphires are, but the star effect, also known as an asterism, can be seen on other gems such as rubies, garnets, diopside, spinels and tourmalines, too. It is an optical phenomenon caused by fibre-like inclusions, and can only be observed on the polished, reflective surface of a cabochon-cut stone. Chatoyancy is a similar effect caused by the parallel fibrous internal structure or inclusions, which result in the appearance of a narrow line across the gem surface. When this effect is observed on a chrysoberyl, the gemstone is called a cat’s eye, but it can also be seen on quartz, moonstones, aquamarines, tourmalines and more.

9 SOME GEMSTONES HAVE SPLIT PERSONALITIES

Alexandrite, a rare and expensive type of chrysoberyl, can be red or purplishred under artificial lighting in a building, but by the time you walk towards the the sunlight, its colour will dramatically change into green or bluish-green. Colour change based on light source is a highly desired optical effect in gemstones, and exhibited by several other kinds of gemstones, including garnets, apatites, sapphires, fluorites and diaspores.

10 DIAMONDS ARE NO LONGER NATURE’S HARDEST MATERIAL

In recent years, two new natural minerals have been discovered to be harder than diamonds. They are wurtzite boron nitride, which has a similar structure to diamonds but not made of carbon atoms; and ionsdaleite, a hexagonal diamond made of carbon atoms that are arranged in a different shape from diamonds.

11 CHINESE EMPRESS DOWAGER CIXI WAS MAD FOR TOURMALINES

A traditional lucky stone to the Chinese thanks to its name “bi xi”, which sounds like “bi xie” (to ward off evil), the tourmaline was a favourite of Qing Dynasty’s Empress Dowager Cixi. She especially adored the pink variety, and some 120 tonnes of gemgrade tourmaline were mined between 1902 and 1910 from the Pala mines of California to be crafted into fine jewels, snuff bottles and other objets d’art for her. The trade between the two countries was facilitated by Tiffany & Co. Rubellites are outstanding pink or red tourmalines that display luscious colours, which stay true in artificial light as well as daylight.

12 THE ARGYLE MINE PRODUCES ONLY A PALMFUL OF PINK DIAMONDS ANNUALLY

According to Far East Gems & Jewellery’s Tay, the amount of pink diamonds larger than half a carat mined annually from the Argyle Diamond Mine is so miniscule that they could all fit onto one palm. This fact is made even more astounding when you consider that 90 per cent of the world’s pink diamonds originate from this mine.