Opal is an extremely precious gem, named for its appearance and luster. It looks like a cat's eye, and it is also the rarest golden emerald. As the saying goes, rare gems are naturally expensive, and Sri Lanka is the only country that produces them in the world. Generally speaking, there is no opal above 10 carat in the domestic market. You can imagine how precious it is. However, what kind of opal makes it so rare?
Opal is one of the most precious jewels and jade. It is listed as one of the five famous gems in the world. Its unique cat's eye effect is flexible and bright, with gold, jade and cat's eye effect as the main effects.
Cat's eyes are mainly produced in Sri Lanka, Brazil and other places, especially the most famous Opal in Sri Lanka, which is especially loved by collectors.
Sri Lanka is a magical place, with not only rubies and aquamarine, but also a unique golden green opal. Honey yellow opal is not only the rarest opal, but also produced in Sri Lanka. In the spotlight, it will open and close like a cat's eye, which is amazing.
In this magical country, there are all kinds of precious stones, rubies, diamonds, zircon and spinel besides opal, which is regarded as a national treasure. These products are usually of good quality and are respected by people all over the world.
In fact, cat eyes are not only produced in Sri Lanka, but also in Myanmar, Brazil, Madagascar and other places. Due to different ingredients, there are golden yellow, honey yellow, gray green, brown and brownish yellow.
It is generally believed that honey yellow and golden yellow are the best opals. But now there are many fake opals on the market, especially those with cat's eye effect, instead of turquoise, which is commonly used as opal. But the price and collection value are so great that everyone must be careful to avoid taking medicine in the pit.
Cat's eye), that is, "golden emerald with cat's eye effect". Also known as cat's eye, cat's eye, cat essence and oriental cat's eye, it is a rare and precious jewelry variety. Also known as Alexander's cat's eye, it has both discoloration and cat's eye.
Opal is one of the rarest and most precious emeralds. Only Sri Lanka is produced in the world, and the price is quite expensive. It is difficult to see anything over 10 carat in domestic shopping malls. Opal is named because it shows the same light phenomenon as cat's eye, which is elastic and bright and can change with the intensity of light. This optical effect is called "cat's eye effect".
Opal belongs to chrysoberyl in mineralogy and belongs to chrysoberyl class. Emerald is beryllium-containing alumina with the following chemical formula: bismuth borate. It belongs to orthorhombic system. The crystal form is usually short column or plate.
Strictly speaking, "cat's eye" is not the name of a gem, but an optical phenomenon on some gems. That is to say, a hemispherical gem will have a narrow and bright reflection on its surface under strong light, which is called "cat's eye flash" or "cat's eye live light". Then it will be named after what the gem is. If a gem is in season, it is called "quartz cat's eye"; If it is emerald, it is called "emerald cat's eye". There are many kinds of gems that may have cat's eyes. According to statistics, there may be as many as 30 kinds. In addition to quartz cat's eyes and golden green cat's eyes, there are mainly pyroxene cat's eyes and aquamarine cat's eyes on the market. Because the golden-green cat's eye is the most famous and precious, it is also called' cat's eye' for short, and other cat's eyes can't call it that.
Opals are often called "noble gems". Together with all kinds of gems, it belongs to one of the five precious and high-grade gems in the world. Yanshi mainly occurs in gas hydrothermal deposits and pegmatite veins. The most famous opal in the world is produced in Bula and Goyle in southwest Sri Lanka. Brazil, Russia and other countries also have opals, but they are very rare.
Opal belongs to chrysoberyl in mineralogy and belongs to chrysoberyl mineral. Transparent to translucent. Lubricate the glass. The refractive index is 1.746- 1.755 and the birefringence is 0.008-0. Dichroism is obvious, and the dispersion rate is 0.0 15, which is not isotropic. The hardness is 8.5, and the density is 3.71-3.75g/cm3. The shell is broken. The difference between cat's eyes like opal and artificial cat's eyes.
Opal has many colors, such as honey yellow, brown yellow, wine yellow, brown yellow, yellow-green, yellow-brown, gray-green and so on. Honey yellow is the most precious. Transparent to translucent. Lubricate the glass. The refractive index is 1.746- 1.755 and the birefringence is 0.008-0. Dichroism is obvious, and the dispersion is 0.0 15, which is not isotropic. The hardness is 8.5, and the density is 3.71-3.75g/cm3. Shell fracture, secret welding array cleaning.
Gems that can produce cat's eye effect in nature include tourmaline, beryl, apatite, timely stone and kyanite. But they are not as precious as gold and green cat's eyes.