How to buy a firestone opal gemstone. How to identify fake opal?
Fire opal is a kind of opal that includes red, orange, and yellow colors. Since a lot of fire opals are found in Mexico, they are sometimes called Mexican. How…

Continue reading →

The world of gems
The term cabochon is derived from the ancient French word Caboche, a head and a relatively flat stone that is formed with a smooth, polished, dome-shaped front surface, unlike faceted…

...

How to buy a firestone opal gemstone. How to identify fake opal?
Fire opal is a kind of opal that includes red, orange, and yellow colors. Since a lot of fire opals are found in Mexico, they are sometimes called Mexican. How…

Continue reading →

Do you know everything about gems or jeweler tips
WHAT TO WEAR? Marilyn Monroe's catch phrase, "Girls' best friends are diamonds!" Seems never to be questioned! These class "A" stones are valued above all because of their absolute transparency…

Continue reading →

Artificial diamond substitutes.

After all, if there is a new, indistinguishable from a diamond cheap substitute for it, then the number of fraudsters sharply increases, and because of the uncertainty of buyers, the demand for diamonds may drop sharply, and the price will fall behind demand. Worse still, the stone, fraudulently issued for the sale of a diamond, which is indistinguishable at the beginning from a diamond, can later be somehow “exposed”, which means the loss of gem buyers. Why is the diamond so beautiful? The higher the refractive index of light in a crystal, the more it shines. Another important is the play of colors, depending on the dispersion of light in the crystal. Under the dispersion it is understood that in a crystal for a ray of light, depending on the wavelength, a different refraction, which creates a rainbow of colors when the crystal is illuminated. Cutting a diamond, turning it into a diamond, enhances the effect, the edges collect and reflect the incident light. The most primitive fake diamond – various types of glass. But glass is dim compared to diamond. Even Swarovski Crystals, no matter how much better they are than just cut glass. From the beginning of the 20th century, when they learned to “make” rubies and sapphires, colorless sapphires were also considered as diamond substitutes, but compared with diamond, they are also dull. After World War II, the first diamond substitute to hit the market was rutile. Rutile is titanium oxide. In nature, it is polycrystalline and opaque. But if it is cleaned of impurities and melted down (as artificial rubies are made), then a transparent, colorless crystal is obtained (if you know how to do it). The crystals obtained are refracted almost like diamond, and the dispersion is even greater than that of the diamond, but the crystals themselves are very fragile, which makes their processing difficult and makes the resulting stones short-lived. In addition, the stone is very fragile. The fabulite, or strontium titanate, is very close in refraction to diamond, and in dispersion it slightly exceeds it. But he, like rutile, is very fragile and fragile. Produced since the mid 50s. Cubic zirconia, or chevalite, or CZ is cubic zirconium oxide, one of the most spectacular diamond imitations. It was synthesized in the USSR at the Institute of Physics of the USSR Academy of Sciences (FIAN), therefore, we received the name “fianit”. Abroad in the course of other names. It is often called zirconium or zircon. But neither zirconium metal nor the natural mineral zircon fianit has nothing in common. Cubic zirconia – solid (8.5), very heavy, transparent, colorless, with a strong dispersion (more than that of a diamond) stone, in appearance very reminiscent of a diamond. His refractive index is almost the same as that of a diamond. The way to distinguish it from diamond is very simple – it is opaque in X-rays. If you do not have an X-ray machine at hand, you can put a stone in a glass of clean water. A diamond will become invisible, a fianit will not. They say that if you breathe on a stone, then the fianit will sweat, but a diamond will not. In addition, there are devices that allow to measure the thermal conductivity of the stone. Diamond is very heat conductive, fianite is not. Density of cubic zirconia more than the density of diamond. Yttrium-aluminum garnet (YAG) is durable; its refractive indices and dispersions are noticeably lower than those of diamond; they are produced mainly by the Czochralski method, by pulling from the melt. This garnet is quite durable and very well polished. Often used for the production of rhinestones-copies. It was made from a copy of the famous pear-shaped diamond Elizabeth Taylor (69.43 carats), presented to her by Richard Burton. The cost of rhinestone turned out to be comparable to insurance against the loss of a stone, which Elizabeth Taylor paid for “socks” for one evening ($ 3,500 for a stone, $ 1,000 for an evening insurance). At the same time, only a specialist could distinguish it from the original using special equipment. Although, if they were put nearby – the difference was noticeable. Gallium-gadolinium garnet (YYY) is not very durable, and its refraction is slightly less than that of diamond, and the dispersion is almost like diamond. It is produced, like IAG, according to the Czochralski method, mainly for the needs of the electronics industry, and only a few small laboratories produce it for the needs of jewelers. It is much more expensive than YAG, more expensive and its production. It is very similar to diamond, but it has a much lower strength and a greater density than a diamond. Zircon is the only common colorless natural stone that has a play of color and light, so that it can be confused with a diamond. Zircon has the same dispersion as diamond, but its hardness is lower (6.0–7.5). Experts recognize zircon by bifurcation of the back edges due to the strong birefringence of the stone, which is not possible in a diamond. Scheelite is sometimes found in the form of transparent, colorless debris. A good cut gives these stones an attractive look and makes them very similar to diamond. Scheelite has a low hardness (4.5–5.0) and is too rare to be used for mass production of jewelry. People invented a lot of diamond substitutes. Many of them are very, very similar. But there is no one that would be indistinguishable from a diamond.

Artificial diamond substitutes.
After all, if there is a new, indistinguishable from a diamond cheap substitute for it, then the number of fraudsters sharply increases, and because of the uncertainty of buyers, the…

...

Do you know everything about gems or jeweler tips
WHAT TO WEAR? Marilyn Monroe's catch phrase, "Girls' best friends are diamonds!" Seems never to be questioned! These class "A" stones are valued above all because of their absolute transparency…

...