Jade is the English name given to two distinctly different substances – Nephrite and Jadeite.
Nephrite is the famous New Zealand Maori greenstone and the material carved by the Chinese for almost 5,000 years.
Jadeite is the rarer and harder material (a sodium aluminium silicate) which eclipsed Nephrite in China during the 18th century.
The best Jadeite, known as ‘Imperial Green’, has a rich, vivid green colour and astounding clarity, with fine carvings selling at specialist auctions in the Far East for millions of US$. Gram for gram, fine jadeite can be worth more than diamonds. But Jadeite carvings can also be bought from as little as a few pounds.
Ping Ping only uses Jadeite.
There is no objective system for valuing jade precisely. The value of an individual piece relies on its colour tone, how even its colour is, translucency, texture, clarity, amount of flaws and inclusions in the stone and how well it has been cut.
No, Jadeite can range in colour from red, yellow and honey coloured, to lavender, white (known as ‘ice’ jade) and even black.
Being actually harder than steel (around 7.5 on the mohs scale of hardness) jadeite has to be worked using diamond tipped tools and saws.
Jadeite is generally extracted from open-cast mines or collected in the form of boulders from river beds.
China is the traditional home of the jade trade and in Mandarin, the word ‘Jade’ can mean any material that is carved. Thus many Chinese dealers sell materials such as aventurine and serpentine as ‘jade’- often calling their products names like "Korea jade" and "New jade" (serpentine) or "Indian jade" (aventurine). While such dealers are not necessarily intending to cheat their customers, this situation can be misleading for inexperienced buyers and we have seen some importers selling (innocently or not) what they claim is ‘jade’ when it actually other, inferior materials.
Enhancing the colour of jade is an ancient practice which has been elevated to a science in the 21st century. Colours are injected under pressure with the jade heated to a certain temperature so as not to damage its molecular structure. Treated in this manner, the colours are permanent and will not fade. Ping Ping does stock some items made using colour-enhanced jadeite and these are always clearly marked as such. Jadeite can also be clarified using a specialist process to remove impurities and improve its appearance.
However, buyers should be aware of coloured items which are not actually jade or which have been cheaply dyed. Some unscrupulous dealers will sell colour-enhanced jade as ‘Imperial Jade’: The clue is usually in the price as natural imperial jade is extremely expensive (see above).
Chinese mythology believes that Jade is ‘descended from Heaven’ and so is an extremely lucky material. But jade has numerous properties ascribed to it by different cultures. The Chinese say that wearing jade brings wisdom, peace, harmony and focus on spiritual matters; The Spanish Conquistadors believed that it helped cure kidney problems. New Age practitioners say it aids dreaming and helps illuminate a wearer’s true path, as well as promoting relaxation and the efficient completion of tasks. It is also said to be an extremely ‘balanced’ stone. Many Chinese people wear (or display in their cars) lucky and auspicious symbols and figures carved out of jade for luck, good fortune and safety.
Determining whether a piece of jade is really jadeite and whether or not it has been coloured or clarified and then trying to judge its value takes years of experience. However, there are a couple of ‘tricks of the trade’ you can use when buying for yourself.
The first thing that most people do when buying jade is feel it to make sure it is cold. This at least tells you that it is not plastic! Be aware that jadeite can heat up under lights or in direct sun light: It will cool rapidly when removed from the heat source though.
Being very hard, real jadeite will have no trouble scratching glass – many reputable dealers will offer a sheet of glass so that you can test this.
Shining a light through a piece of jade (or holding it up to a light source) will reveal its translucence – one of the most important qualities of fine jade.
If you see any ‘bubbles’ inside the item, it is probably glass.
If you suspect that someone is trying to sell you Serpentine as Jadeite, you should be able to scratch it with a steel blade – although the vendor probably won’t be very happy about you trying this!
Other tests – not really practical outside a laboratory – include flame testing the material, inspecting it in ultra-violet light and measuring its specific gravity, as well as inspection of its molecular structure with a microscope. If you are considering buying an expensive piece of Jadeite in Hong Kong, the seller may agree to have the piece certified in a local laboratory if it has not been done so already.
The famous jade markets of Hong Kong, Guangzhou and Taipei vary wildly in the quality of jade items on offer so are the ideal places to visit in order to learn more about this fascinating material.
Finally, the art of jade buying is based partly on science, instinct, experience and, in large part, trust, so ask yourself if you trust the vendor you are buying from. If not, walk away.
Naturally occurring pearls are now so rare that they are priced out of the reach of all but the richest of collectors.
Found in remaining numbers only off the coasts of Australia and some Middle Eastern Countries, natural pearls are found at the rate of only three or four per ton harvested, with perfect pearls being even rarer.
Therefore, virtually all pearls used in jewellery these days are cultivated by inserting a tiny bead made from polished shell into a specially bred oyster or mussel – in fact a specially bred hybrid of the two creatures is most commonly used.
Irritated by the bead, the mollusc surrounds it with a coat of calcium carbonate to form nacre (a.k.a mother of pearl). After anywhere between six months and seven years (depending on the species of mollusc and the product being made) the oyster will be removed from the water and opened to reveal a pearl.
The science of cultivating pearls was perfected by Japanese scientists in the 1930s. Using species of mollusc which could survive in a lake was found to be more convenient and cost effective than growing pearls in the sea and so the term ‘Freshwater Pearls’ was born.
Most of the pearls offered for sale these days are freshwater pearls. Originally cultivated in Japan, most notably in the famous Lake Biwa, production has almost entirely been moved to China, especially in the area around Shanghai, since the Japanese industry fell victim to increased water pollution.
Some types of pearl, such as South Sea, Tahitian and Akoya, are still cultivated in salt water lagoons but these are considerably more expensive.
The desirable lustre and iridescence of a pearl is caused by light refracting off the different layers of nacre that have been built up. Pearls can occur naturally in many different colours although many are dyed for uniformity. Being an organic substance, pearls absorb dyes well and so the colour will not rub off and should not fade, although certain colours may lighten if exposed to strong sunlight for long periods.
The value of a pearl depends on its size, skin quality, lustre and shape – with perfectly round being the most desirable - while a particular string is valued on how close its pearls are to each other in size and colour. The most expensive of all cultivated pearls is the South Sea Pearl, which is generally large (up to 14mm) and can be found in several different colours, including black and gold.
Being a natural material, a pearl’s surface and iridescence can be damaged by contact with cosmetics, perfume or even perspiration so always follow the old jeweller’s maxim, which says a pearl necklace should be: Last on, first off.
Pearls should be worn regularly to allow them to breath.
Do not try to clean pearl necklaces using an ultrasonic cleaner as this may damage them.
Wipe pearl jewellery with a clean cloth before putting them away.
Ideally, pearls should be stored in a velvet wrap which allows them to lie straight, not coiled up as this can weaken the stringing.
If displaying pearls in a cabinet or shop window, do not let them be exposed to direct sunlight or heat for long periods. A small glass of water hidden in the display can help humidify them.
Expensive pearls should ideally be restrung by an expert every one to two years.