Blue and green are two of the most popular colours with people and with nature – the sea, rivers, the sky and plants are all green or blue or turquoise, a greeny-blue. Turquoise is the colour of the open sea. It is not a hard colour to like and it fits into most colour schemes.
Turquoise is not a especially rare gemstone, but it is rare in its finest state. It is mined in many countries including the USA, Iran, India and China. The word turquoise derives from an old French word for Turkey or Turkish, because it was first imported into Europe from Iranian or Persian mines via Turkey.
Turquoise is easily smashed and is only slightly stronger than glass, having a hardness of 6. Turquoise is one of the oldest mined gemstones and still, most of the world’s mines are small and hand-operated.
Some of the Iranian mines are 2,000 years old and still being worked. However, the oldest mines are on the Sinai Peninsular and they are known to be at least 3,000 years old as they were worked in the era of the pharaohs.
The colour varies through greens and blues because of the existence or minerals. If there is more copper present the stone will be bluer and if there is aluminium or iron, it will be greener.
Iranian turquoise is some the best quality in the world and is used mainly in the jewelery industry. Turquoise from some other places, like the south-western states of America, is of lower grade and is too chalky and powdery for this use.
Regrettably, chemists have discovered ways to enhance this gemstone, so that unless you are an expert or buying from a reliable source, you could easily end up purchasing poor grade turquoise that has been treated. This is the case with other gemstones too.
Some of the tricks that they get up to are:
Chemicals can be applied to intensify the natural colour of the gem
Resin can be soaked into the pores of porous, friable, low-grade turquoise to ‘stabilize’ it – ie stop it flaking and falling apart.
Completely untreated, natural turquoise of pleasing appearance is very rare and so very expensive. It would be very hard to impossible for a layman to detect whether a stone has been treated or not, but you are not likely ever to come across any.
Whatever, quality of turquoise you have, you will have to look after it because it is quite soft, easily scratched and fairly easily crushed to powder.
Therefore, do not leave it to rattle about in your bag and store it wrapped on its own in a cool, dark box. Extremes of temperature may harm it as well. Turquoise is naturally porous, even if it has been drenched in resin, so do not permit oils or perfumes to soak into it.
If you have to wash a turquoise, you will need nothing but a soft fabric and warm, but not hot, water. Dry the stone right away after washing with a second soft duster. Be careful not to score the surface with the dirt that you are cleaning off.
Owen Jones, the author of this piece, writes on a number of subjects, and is now concerned with Baby Birthstones. If you would like to know more, please visit our web site at Jewellry and Watches.