ruby

Ruby is mainly produced in marbles of deep metamorphic rock systems, produced in calcium feldspar, vermiculite and oleracite pegmatites, produced in strength stratigraphic plagiarism complexes, produced in basalts, produced in gneiss, granites, and mica schist. The famous production areas include Mogu, Afghanistan, the former Pamir region of the Soviet Union, Hunsa, Thailand, Vietnam in northern Pakistan, etc. According to the different origins, rubies can be divided into the following categories:

1. Myanmar ruby: Myanmar is the most famous place for ruby. Myanmar ruby ​​has been very famous since ancient times. Especially a ruby ​​called "Pigal Blood Red" produced in the Mogu region in northern Myanmar is evenly ranked among the top of ruby. It is bright and dazzling, just like the blood on the chest of a local pigeon bird, so it is named "Pigal Blood Red". Myanmar ruby ​​is unevenly distributed in color and often has a flocculent shape of different thicknesses, also known as the "molasses-like" structure. This structure was once the identification feature of Myanmar ruby. In addition, Myanmar ruby ​​is rich in rutile inclusions.

2. Thai Ruby: Thailand is also an important producer of rubies. Most Thai rubies are darker in color, ranging from slightly purple-red to brown-red. In addition, they almost lack rutile enclosures, so there is no star-light ruby ​​variety.

3. Sri Lankan rubies: Ruby is slightly lighter in color, mostly pink, and contains a large amount of rutile and zircon inclusions.

4.

Vietnamese ruby: The color is between Myanmar and Thai ruby. The overall color is darker than Myanmar ruby, and lighter than Thai ruby, and it is purple-red and light purple.

5. Chinese rubies: Currently, there are seven or eight rubies produced in my country, mainly including Qinghai, Anhui, Xinjiang, Yunnan, Heilongjiang and Qinghai provinces and regions. Among them, Yunnan rubies are the best ruby ​​minerals discovered in China in recent years.

There are only a handful of rubies produced in the world, mainly including Myanmar, Sri Lanka, Pakistan, Thailand, Cambodia, Vietnam, China and other East Asia, South Asian countries and Australia. The most famous ruby ​​production area is the Mogou region in Myanmar. The Mogou region is located east of Dabekachin City in northern Myanmar, with a mineralization area of ​​nearly 1,000 square kilometers. It is the most famous "Mogou Gem Belt" in the world. Here, native rubies are stored in magnesium calcite skarn (i.e. ruby ​​silicery marble). After weathering and destruction, minerals such as weather-resistant corundum remain in the riverbed, forming famous ruby ​​and spinel residue-sloping ore and alluvial ore. Its economic value is extremely high. Mogou is an ancient crystalline rock (Precambrian gneiss) area, with some granite bodies interspersed.

Simple identification of sapphire and origin

The biggest feature of sapphire is uneven color. It can be seen that the parallel six-sided cylinders are arranged in a straight ribbon and growth pattern with different depths. The polyscopic double crystal development is common, and the louvered double crystal patterns are often cracked along the double crystal surface. The cracking principle is strong. In addition to the above common characteristics, sapphires from different origins in the world also have their own characteristics due to different origins.

According to different geological causes, there can be divided into two categories: one is sapphire produced in Myanmar, Sri Lanka and Kashmir, India. The other is sapphire produced in Australia, Thailand and China.

Sapphires produced in Myanmar and other places are bright blue because they contain titanium, and are composed of silk-like rutile and fingerprint-like liquid inclusions. Silk-like rutile inclusions can produce six- or twelve-fire starlight, which is a high-quality gem variety. Sapphires produced in Australia, Thailand and China contain more iron and are colored by iron. Therefore, the gemstones are very dark in color, and the faceted gemstones are not reflective. They generally need to be heated and processed before they can be used.

The characteristics of sapphires from different origins are briefly described as follows:

Indian Kashmir sapphire is blue of cornflower, that is, indigo blue with slightly purple. The color is bright and bright. The foggy inclusion has a milky white reflective effect. It is a high-quality sapphire variety. However, since the mining area is located at the northwest end of the Himalayas, with an altitude of more than 5,000 meters and is shrouded in fog all year round, it has not produced in recent years.

Myanmar's Mogo sapphire is produced in the same mining area and has the same characteristics except for the different colors. Its enclosure is as follows: silk-shaped rutile enclosures, densely arranged parallel six-sided cylinders, crossing at 60 degrees and 120 degrees. If the vertical silk-shaped enclosure is cut, it can appear six- or twelve-range starlight after being polished into arc-sided gems; the bubbles in the inclusion space of the fingerprint-shaped liquid enclosure occupy a small area, about 30%; solid enclosures are commonly found in corundum, spinel, uranium-burned chlorite, apatite, etc.

Sri Lankan sapphire and ruby ​​belong to the same mining area. Except for different colors, the other characteristics are exactly the same. The inclusion body is as follows: the silk-like inclusion body is similar to the Burmese sapphire, the difference is that the fibers are thin and long, and can present six-shot starlight; the liquid inclusion body is in an amorphous layered cloth or fingerprint-like cloth; the solid inclusion body includes zircon, apatite, black mica, etc.

Thai sapphire is black blue and light gray-blue. There is no silk-like inclusion in the crystal, but the fingerprint-like liquid inclusion develops. The most characteristic is that there are cracks spreading like lotus leaves around the black solid inclusion. Three groups of polyscopic double crystals develop, and the cracks crack along the double crystal plane.

Chinese sapphire. In the 1980s, many sapphire deposits were found in basalts along the eastern coast of China. Among them, Shandong (Changle) sapphire has the best quality. The crystals are hexagonal barrel-shaped and have a large particle size, generally above 1cm, and the largest one can reach several kilocarats. Because of its high iron content, sapphires are mostly in indigo, blue, green and yellow, which is close to carbon black. Indigo is the main color. There are very few inclusions in gem-grade sapphires, and in addition to black solid inclusions, fingerprint-like inclusions can also be seen. There are no silk-shaped rutile and diffuse liquid inclusions. The straight ribbon in the sapphire is obvious, and the pooled double crystals are not developed. The growth line of parallel hexagonal cylinders can be seen on the outer edge of the large crystal. Shandong sapphire is a high-quality sapphire due to its lack of internal defects.

Heilongjiang Province sapphire. It is bright in color, transparent blue, light blue, gray-blue, light green, rose-red, etc., and does not contain or contain less inclusions and can be used without changing the color. The disadvantage is that the particles are small. Sapphires produced in Hainan Island and Fujian are similar in characteristics. Generally, crystals with particle sizes less than 5mm are beautiful and transparent in color. Except for the very small amount of gas-liquid inclusions and straight simple double-crystal patterns, they rarely contain other defects. However, the outer edges of crystals with particles greater than 5mm contain a layer of milky white, opaque, and parallel hexagonal cylinders to varying degrees. Three groups of parallel rhombus in the crystals develop. There are also many aggregate gaps and silkworm seed-like rutile inclusions.

Jiangsu Province sapphires are beautiful and transparent in color, mostly blue, light blue, and green. However, when sprayed out of the surface, the eruption force of the volcano is strong, so the sapphire crystals often crack along the axis and are in a thin plate shape, so it is difficult to obtain materials.

Australian sapphire. Australia is a place of origin for sapphires with rich production. However, due to the high iron content, the gemstones are dark in color. They are mostly dark blue, yellow, green or brown near carbon black. They contain dust-like inclusions. Their gemstones are the same as those of Thailand and China, and they all need to be changed before they can be used.

Identification of rubies, Myanmar Mago Ruby. Gems are mostly pigeon blood red, rose red, and pink. The colors are bright but uneven. Straight ribbons are often seen. The multicolor is obvious. If you observe the gems from different directions with the naked eye, you can see two different colors. The development of polyscopic double crystals can see straight louvered double crystal patterns. The cracks often crack along the surfaces of three groups of polyscopic double crystals. The gems contain the following inclusions to varying degrees: silk-shaped rutile inclusions; generally fibrous rutile inclusions parallel to the hexagonal cylinder of the ruby ​​crystals, forming three groups of surface nets with intersection angles of 60 degrees and 120 degrees. When parallel to this group of packages

When the surface mesh is cut and polished into arc-surface gems, when light shines on the arc surface, six-star light will appear, namely star-light ruby. If the fiber inclusions are irregular and densely stacked, they will appear translucent milky white flocculent patches. The diffuse gas-liquid inclusions are distributed in the gems, and the gas-liquid area is small, about 30%. If the gas-liquid inclusions gather together and spread in a fingerprint-like manner, it is called fingerprint-like gas-liquid inclusions. Short columnar, granular mesh inclusions: rubies often contain mineral inclusions such as spinel, calcite, cylindrite, hematite and other mineral inclusions. The edges and corners of these small minerals are smooth due to melting.

Sri Lankan Ruby. The characteristics of gems are similar to those of Burmese rubies, but they are lighter in color and have a higher brightness. In addition to having similar characteristics to Burmese rubies, the inclusions in Sri Lankan Ruby also contain two unique mineral inclusions: apatite inclusions, which are hexagonal columnar, smooth edges and corners, and appear in a single crystal or group; silk-shaped rutile inclusions are slenderer than silk-shaped rutile inclusions in Burmese rubies.
Chapter completed!