Myths and legends

How to distinguish natural turquoise from artificial one?

In this article we will talk about what you need to pay attention to when buying turquoise and what tests you can try to identify a fake. What to look for when observing the appearance: Color can vary from bright blue to green and brownish-green (blue color is created by copper compounds, and the amount of water, aluminum and phosphorus determines the presence of other shades), but find turquoise with a perfectly uniform and It is very rare to find one in a single color. If you see beads of a uniform color and their cost is less than several thousand dollars, most likely they are pressed and dyed. The matrix can be black, brown, yellow and other colors, but it is always at a different height with the turquoise, which creates a relief: drag along the surface of the stone, if you catch on the place where the matrix meets the turquoise, this is a good indicator. You should also pay attention to the price: if the price seems too good to be true, it probably is. If you see a string of perfectly matching beads of the same uniform color, remember that it is very difficult to find something like this in nature and such specimens would be very expensive. Only a gemologist can tell you exactly whether your turquoise is natural, but if you want to make sure at home, there are a number of tests: — Scratch test. Most tests are quite destructive to the stone itself; the scratch test is the least dangerous if the bead is tested on a part other than the most visible part of the stone. Turquoise is a naturally soft stone, but howlite is even softer: this may mean that if the stone scratches too easily, you likely have howlite.
Pin test. It involves heating a pin and placing it on the surface of the stone – the smell of hot plastic will indicate that the beads have been treated with polymers or are imitation. Solvent soak test. Soak the bead in a strong solvent such as acetone or mineral spirits overnight. If the turquoise has been dyed, some of the dye will end up in the solvent. Break test. A destructive method that can be used if you have loose pieces of turquoise. There will be no white voids inside real turquoise, the color will be uneven and combine various shades of blue, whitish, green and matrix. There are also more professional testing options (possible if equipment is available): — Mohs hardness test. One of the most effective tests. The hardness of turquoise is 5-6, magnesite 3,5-4,5, and howlite 3,5. — Magnifying glass test. Look at samples through a magnifying glass for air bubbles or small cracks – air bubbles indicate the object is made of glass, small cracks may indicate synthetic turquoise or imitation from other materials. If possible, you can look at the stone through a Chelsea color filter: if the color appears slightly pink under the filter, it is most likely variscite, if pinkish-red, it is howlite.

Bonus: Can processed turquoise be considered natural?

Natural turquoise may be sold as mined (these specimens are typically fragile and are not used for jewelry), stabilized (the beads may be coated with wax or epoxy resin to reduce the likelihood of the stone breaking during the cutting process), or dyed and treated . As long as this processing is mentioned, turquoise can still be listed as natural, although many unscrupulous sellers do not indicate additional coloring and processing in the information. We are completing a series of articles about turquoise: we learned what types and varieties of turquoise there are, what colors its body and matrix are, how turquoise is processed, what stabilized and processed turquoise is and how to identify a fake. If you still have any questions, leave a comment. Counterfeiting of turquoise began back in Ancient Egypt – craftsmen painted glass with cobalt, copper and other components with a similar tint. Later, high-quality fakes made of porcelain, bone, etc. appeared. In general, any materials with pigmentation identical to the color of brilliant turquoise were used – crushed to a powder, mixed, pressed and polished to a shine. And today there are numerous counterfeits of turquoise on the market.

What is the difference between real turquoise and fake?

Natural turquoise has a certain hardness, density, color, luminescence, waxy luster, as well as a certain structure that can only be seen under a microscope – a light blue background is decorated with dark blue disks, as well as small particles of white shades. In artificial turquoise, bluish particles predominate. The easiest way to identify a fake is one made by surface painting of plaster or plastic. One of the simplest and most proven tests is the hot needle test. Heat a needle on the fire and press on the stone. If the turquoise is synthetic, then the place of contact becomes discolored, or the “stone” is melted like paraffin. Colored quartz and minerals that look very similar to this stone are often passed off as turquoise. Such fakes are much more difficult to recognize. Since natural turquoise has a wide range of physical properties, counterfeit detection is often carried out using X-ray electron microscopy and other professional techniques. Some types of synthetic turquoise have such a similar composition that even experienced specialists have to spend a certain amount of time to distinguish a fake from the original. But most often turquoise is imitated from plastic, since this is the cheapest way to fake it. Unmasking plastic “turquoise” is quite simple with a needle and a burning match. Although it is worth recognizing that such fakes are distinguished by perfect coloring.

The main ways to identify a fake:

  1. Wipe the stone with a damp cloth – painted material may leave traces of paint. If the dye is of high quality and has not left a trace, then you can wipe the stone with a cotton swab and alcohol. Some dyes cannot be recognized even with the use of alcohol.
  2. Fake turquoise will turn black and melt if held over a hot match. Plastic will immediately give itself away with the characteristic synthetic smell of burnt plastic.
  3. If you heat native turquoise, the stone is likely to crack along the veins, so you need to check very carefully and not overheat the natural crystal.
  4. Painted plastic is easily identified with a regular needle – just scratch the stone. If it is easily scratched and sprinkled with shavings or white powder, then it is undoubtedly a fake. Natural turquoise is colored throughout the entire thickness of the stone. And a plastic fake will have a light synthetic base under a thin colored layer.
  5. It is useless to scratch painted faience – no shavings are formed, and the needle can even be rubbed off on the stone, since the hardness of faience is much higher than the hardness of turquoise. The same result will be obtained if you scratch a fake made on the basis of varieties of chalcedony.
  6. When choosing beads or a bracelet made of turquoise, look carefully at the hole for the thread – if the inside of the beads is lighter or darker than the surface, then it is undoubtedly a fake.

A fake stone almost always deteriorates after inspection, so it is better to perform all procedures not from the front, but from the back.

One of the main characteristics of natural turquoise is the size of the stone. In nature, turquoise is found in small pieces. For example, turquoise the size of a walnut is considered very rare. Large stones are unevenly colored. Therefore, if in front of you is a large stone with a uniform color, then it is most likely a fake. Although pressed turquoise, which is made from natural stone chips, is quite common.

Another important characteristic is the price. Turquoise is a precious stone that is quite rare in nature, so turquoise jewelry cannot be cheap. Hence the huge number of fakes on the jewelry market.

What is “turquoise” not made from? Even painted teeth and bones of fossil animals are used. Sometimes this material is called “bone turquoise” on sale. Very often, instead of real turquoise, stones of similar color are offered. Most often this is chalcosiderite, as well as dozens of types of stones with different unfamiliar names, which are significantly inferior in characteristics to the original.

The highest quality substitute for turquoise is turquenite. It is close in its characteristics to natural turquoise, but has a strong porcelain luster.

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