1, Guihei Opal
Black opal is not black, it refers to the color of the embryo, not the color of the surface. The background color of your black opal is dark blue, dark green, grayish black and black. High-quality black opal can emit flashing iridescent light, which is very dazzling. The most famous black opal producing areas in Australia are Mingtaki and Lightning Mountain. The price of expensive black opal is 10 times that of ordinary white opal, and the price per carat is higher than that of diamond. Because of their scarcity, high prices are very stable.
Black opal is mainly produced in Lightning Ridge, Australia. All kinds of black opal have different products and different values. A very important evaluation criterion of black opal is discoloration effect. Opal usually has a typical color-changing effect in gemstones, that is, when it is rotated under a light source, colored spots can be seen, and colored ones have always been loved by the world. Usually, the discoloration of high-quality opal is uniform and complete, and the type and chromaticity of discoloration are the key to evaluation.
2.fire opal
The color of fire opal ranges from yellow to red, and bright red is the most expensive one. However, the color change of fire opal is not obvious, and sometimes it has light green fluorescence, high quality, more transparent and glass-like luster.
Fire opal is the most popular variety in the American market, and the appreciation of fire opal in the United States is rising to a crazy level. 3. Bai Gui Opal
The background color of Bai Gui opal is very light, so when it is processed into jewelry, it is generally necessary to use back-sealing inlay to maximize the effect of color change. Well, Bai Gui opal is the strongest color change.
Therefore, it is also the target of high-priced pursuit. 4. Your jelly opal
Your jelly opal is a variety with half of your black opal. The transparent blue-gray background shows amber body color, showing a beautiful blue-purple change. In fact, your jelly opal is quite cost-effective, but the color change of this opal is usually not very strong. If you can encounter a strong color change, you must not miss it.
Opal is red, orange, yellow, blue, purple, green and light blue from high to low. Red has the highest value, including purple and orange tones, but the combination of strong and bright crimson, orange and black background is the best. In addition, the common color changes of black opal are blue and green. Isn't opal the best if it is only blue and green? Not exactly, if the change of color gives people a good image of high quality, it is also the most valuable. In addition, the greater the range of color change, the higher the value.
If the color changes of stains interweave to form a special style, they will also be regarded as collectibles, such as national flag style and peacock feather style. To measure the value of opal, besides color change, it also includes some common elements of gemstones, such as clarity, whether there are cracks or other inclusions, and weight is also the key. The higher the weight, the higher the value. And yield reduction,
Australia's gravel back opal has also attracted much attention. Black opal is attached to the parent rock, while gravel opal is attached to dark brown sandstone. At one time, the price of gravel-backed opal was only one-fifth of that of black opal, but with the decline of high-quality black opal production, the price of gravel-backed opal with beautiful discoloration effect has also increased a lot. There are also producers who collect thin opals that cannot be independently made into jewelry, and use it with glass or black backing to make laminated opals and three-layer assembled opals. These are artificial products with low value.