Turquoise is an attractive precious stone that makes exquisite silver turquoise jewelry. Technically it’s a combination of aluminum and phosphates with some traces of copper oxide, which gives it its blue color, and manganese oxide, iron, calcium and zinc. The gem’s green color comes from the aluminum or iron and yellow from zinc. The most common color is green for turquoise stones, and in fact blue gemstones often transform into green when exposed to sunlight for a long time. Different mixtures of these elements give the gemstone its array of colors, with the most valued being those with a deep blue color and yellow gems having the lowest value. High quality stones, Persian turquoise for instance, don’t tend to fade and maintain their lovely blue color for many years.
Some gems have a main color with a spider web matrix on the surface of the gem consisting of lines of a different color. The cause of this is irregular dispersal of the different elements present in the gem and the lines may be brown, yellow or black in lots of patterns. However unmarked gems are more highly prized than those with a spider web matrix though turquoise stones of intense blue color, even with spider web matrix, are more sought after than yellow or green unmarked stones. Natural stones of a pure color, that is without a spider web matrix, are rarer and are very highly valued.
Treating Turquoise
About 10% of turquoise used in jewelry is the naturally occurring, finest quality gemstone. Over 85% is treated from rough, soft turquoise so that it hardens enough for use in jewelry. This process also increases durability and develops the color of the gemstones. Turquoise from some countries, i.e. China, is always too soft and requires treatment. In spite of this the treatment produces attractive gemstones, which, though less prized than untreated gemstones, still make wonderful jewelry. Treatments enhance the gemstones color and also makes them tougher which makes them last longer. A process that is used to improve the color involves injecting epoxy resin that contains a dye into the stone. The color is durable and will remain unchanged. Chinese turquoise is hardened by injecting the gemstones with a liquid plastic. A further technique is to inject epoxy resin without a color that will harden the stone without changing the color.
Simulated turquoise can be made from a base of liquid plastic with powdered turquoise. This type of turquoise is naturally very cheap. These imitation gems might be sold as high quality natural turquoise turquoise and are often waxed or coated in plastic.
Looking After Turquoise Gems
Turquoise is both porous and soft so needs to be carefully looked after. It must never be worn at times when scratching can be occur and should be protected from impact at all times. Never wear turquoise jewelry when washing the car or gardening! Keep turquoise jewelry in a softly lined box and never store with other, harder gems which could scratch it. Turquoise gems can soak up liquids so do not let them come into contact with oils, chemicals or hot water and even cosmetics and perfumes. These could be absorbed by the stone which may change color and lose it’s lustre. You can clean turquoise by using mild soapy water and then drying carefully with a soft cloth. Ensure it is completely dry before storing it away and never use an ultrasonic cleaner as they may cause cracking of the stone.
In Conclusion
Turquoise is a beautiful, eye-catching precious stone which is rare and sought after. Even though it definitely does have several disadvantages in that it must be taken great care of and a number of the blue stones can change to green over time, it makes fantastic silver turquoise jewelry as the lovely blue color goes perfectly with the silver. |