2. Multi-flake twins developed, and common louver twins were found. Cleavage often cleaves along double crystal planes.
3, strong color, sapphires around the world have their own characteristics in addition to the above characteristics because of different origins.
According to different geological causes, it 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. Sapphire produced in Myanmar and other places is bright blue because of its titanium content, and contains spun rutile and fingerprint-like liquid inclusions.
Filamentous rutile inclusions can produce six or twelve starlight, which belongs to high-quality gemstone varieties. Sapphire made in Australia, Thailand and China contains a lot of iron, so the color of sapphire is very dark, and the reflective effect of faceted gemstones is not very good. Generally, it needs heating treatment before it can be used.
Extended data
China sapphire. In 1980s, many sapphire deposits were discovered in basalt along the eastern coast of China. Among them, Shandong (Changle) sapphire has the best quality. The crystal is hexagonal barrel-shaped, with large particles, generally above 1CM, up to several kilograms. Sapphire is mostly indigo, blue, green and yellow, which is close to charcoal black because of its high iron content.
Mainly indigo. There are few inclusions in gem-grade sapphire, except for black solid inclusions, fingerprint inclusions can also be seen. There are no spun silk rutile and dispersed liquid inclusions. In sapphire, the straight band is obvious and the polycrystalline twin is not developed. The growth lines of parallel hexagonal cylinders can be seen at the outer edge of large crystals. Shandong sapphire belongs to high-quality sapphire because of its few internal defects.
People's Network Art Network-Teach you a simple sapphire identification method (Figure)