The chemical composition of agate and chalcedony is the same, that is, all silica: SiO2, which is some form of ultra-fine crystal or cryptocrystalline quartz, is extremely small and can only be seen with the naked eye under a high power microscope. The Mohs hardness of umma and chalcedony is 7, some chalcedony can reach 8 and jade is 7, so agate and chalcedony are very hard stones that can be applied to a variety of jewelry. The density of agate and chalcedony is 2.65-2.66g/cm?, and jadeite is 3.24-4.43g/cm?, chalcedony should be lighter than jade. The refractive index of chalcedony is 1.544-1.553, which is slightly lower than the refractive index of jadeite 1.66 (dot). In the market, people use a quartz block that is transparent and has only one color, that is, a structure without a band, called chalcedony: Striped called agate: A) Onyx The typical ring-like structure is very popular and there are many things that are enhanced in color. Pay attention when buying. B) skeining agate Wrapped onyx is known for its elegant design, and Mexico is one of the first places to produce this ingredient. Many of these materials are made into men's products such as men's rings, which are very tasteful. C) dendritic, mossy and feathery agate These agates have one thing in common, they all contain mineral elements of any color, but have a rough tree or dendritic pattern. Relatively speaking, those that look more like plants or feathers are called moss or feathery agate. D) Landscape agate Some of the most valuable are those that show people a landscape picture that seems to be taken from nature. Chalcedony As long as it is a color of translucent cryptocrystalline quartz, it is called chalcedony. The classification of chalcedony is based on the difference in color. The similarities and differences of this color are caused by metallic impure substances in the hidden microcrystals, such as iron, nickel, copper and titanium. There are quite a lot of chalcedony, and here are three kinds of common ones, namely red chalcedony, blue chalcedony and green chalcedony. A) Carnelian It is the most common and most common, and it is the cheapest chalcedony in the chalcedony family. Its color is yellow, orange to rich orange, and some even reddish brown. The transparency can range from almost opaque to highly translucent. A very important feature of red agate is that the enhancement of color is often the only kind of chalcedony that is taken for granted. Remember: Unless it is a special description of the merchant, the carnelian on the market is the result of baking or dyeing, regardless of whether the product has a certificate (described later). The most important reason for the cheapness of carnelian is the result of color enhancement. There is a reason for the conventional staining of carnelian marrow: one reason is that the red color of the natural color is really rare. Another more important reason is that the color of the carnelian is easy to carry out. The red color of the red chalcedony is caused by the oxidation of iron in the stone. Generally, as long as the stone is properly grilled, you can get a rich red color. Of course, there are problems with the level of barbecue technology during this period. Sometimes even the stone is placed in the strong sunlight to strengthen the red color of the chalcedony! Enhanced red I have heard people say this: This red agate is 50 years ago and must be a natural primary color. . . . Oh, wrong bird. . . Didn't anyone see that many of the old agates in the past were almost the same color: dark red! The dark red tone is the result of iron oxidation. The color is dark and cunning, oh, it is estimated that the previous baking color technique is not as developed as it is now. Of course, in addition to baking color, the red chalcedony also has dyeing. In order to obtain a certain color effect, there are many dyed red chalcedony. There are many dyed chalcedony on the market today. At present, the most famous origin of the world's red chalcedony is India, of course, mostly baked. If the color of the carnelian is as common as the above, it will definitely bring a headache to collectors who only pursue natural primary colors: how to distinguish the color of the baking and the natural color? In general, the chalcedony of the enhanced color is more boring than the chalcedony of the natural primary color, and lacks agility. This is a change in the structural characteristics of the stone of chalcedony. The color medium of the stone is a citrate, layered structure with the property of absorbing and excluding water. When the chalcedony is heated, the stone is dry and dehydrated, and the permeability and gloss are reduced. Roasted chalcedony, although the color is eye-catching, can really lose the agility of the natural primary color, looks dull. The round must be smart, the grilled color is rigid The principle is this, but in practical applications, problems will still be encountered. For example, if the opaque chalcedony with high transparency is used to strengthen it, there will be some chalcedony which is no less than the natural primary color. Baked goods. A situation like this is difficult to distinguish from the photos, and the real thing needs to be understood. In a word, the red agate is a thousand feet deep. . . The following example is typical. You will find that the pair in the picture below is much clearer than the pair in the picture above. In fact, the picture below is the enhanced color. The above picture is for the natural primary color, the price is much more expensive than the one below. Blue chalcedony There are all kinds of blue, and each color has its own fans. It is generally named after the origin of the color system. The blue color is deep and light, and some blues have varying degrees of gray or pink tones. The colors of the blue family are varied, from almost colorless to very positive blue. The blue is generally very elegant and deep, much like sapphire. The degree of transparency is also varied. Blue rough At present, the blue chalcedony circulating in the market is mostly dyed blue chalcedony. A small amount of blue chalcedony of natural primary color is also sold. Unfortunately, the quality is really unreasonable. There are only two kinds of dark blue and blue texts, and Taiwan's Hailan knows a lot of people, but unfortunately almost all are dyed. Artificially dyed blue chalcedony, said to be a cobalt dye: Dye blue The difference between natural primary colors and stained specimens. First of all, the natural color map of the dark blue, the purple color in the dark blue, and the color of each one is slightly different. Naturally expensive: about 4w worth: C) Green chalcedony At present, there are several places of green chalcedony in the world, but only one place in the state of Wales in Australia is dominant in quality. Although there is no fear of depletion of resources in this area, the green chalcedony is still the most valuable one among the chalcedony family. Status. A long time ago, because of the scarcity of such mineral resources, many traders in the world often used color nickel or chromium salts (both are green mediators) to dye colorless quartz stone green as green chalcedony. The good news is that the most common green dyes are chromium salts, which can be detected with Charles mirrors. Those similar to the high green emerald green chalcedony can be certificated, indicating whether the stone has been treated or not. Rayon Dyed Printed,Rayon Printed,Rayon Challie,Spun Rayon Shaoxing Shangda Textile Co., Ltd , https://www.shangdatex.com