Sapphire with ruby, is corundum in mineralogy and its chemical composition is aluminum oxide, barrel, cone, discoid and hexagonal crystal, a transparent, translucent, opaque state. Sapphire is also called Turkey stone, its hardness is 9, the proportion is 3.97 ~ 408, refractive index was 1.76 ~ 1.77. According to the different degree of color shades of shades of divided into ocean blue, deep blue, bright blue, water is blue, dark blue, blue and purple, blue, black, blue, gray, green, light blue, aqua blue, light blue, and so on. The difference in the color of sapphire is caused by the amount of trace titanium or two ferric ions in the crystal.

Sapphire in the sunny sky bright blue are best, the color rich and gaudy, the transparency of the sapphire, commonly known as “Kashmir sapphire”. A star sapphire, translucent, in light of the strong, beautiful six shooting stars, called “Starlight sapphire”, referred to as six line, sapphire six line or sapphire line is sapphire in the well-known varieties. Whether the sapphire can produce starlight, depends on the inside of the gem of the light reflecting material, it is closely related to the origin. Sri Lanka sapphire star is particularly good, some of the other regions, and some of the IX sapphire is not the stars.

Sapphire refers to other colors except red outside the corundum gemstone. In addition to blue, there are purple, rose, green, white and other colors. Because, according to the concept of modern gemology, except for the red, the other no matter what the color of corundum, a law – referred to as sapphire. So now in the name of a variety of sapphire before the name of the blue color. Such as “white sapphire, emerald green sapphire, yellow sapphire”, “green sapphire”, “Purple sapphire”, “golden yellow sapphire stone”. The commodity name followed by “white sapphire”, “Oriental Emerald”, “Oriental Topaz”, “Oriental chrysolite”.