The chemical properties of diamond is very stable

Introduced a variety of precious stones
Award in 1999 in China's national stone, the top five are: Xiuyan, Nanyang jade (yu alone), Kunshan Jade (and nephrite), agate, turquoise.
1 Diamond: Diamond is entirely from a single element carbon, mineral crystals formed by crystallization is the only gem stones by the single elements. Diamond is octahedral cleavage, that is, octahedral crystal surface plane of the four directions, the general ladder-like. The chemical properties of diamond is very stable, not easily soluble in acid and alkali. However, in pure oxygen, heated to 1770 degrees, it will decompose. In a vacuum, heated to 1700 degrees, it will be broken down into graphite. Diamonds are transparent, translucent, there are opaque. Gem-quality diamonds, should be colorless and transparent, flawless or very few defects can also be slightly yellow or very light brown, the color is the most precious natural pink, followed by blue and green.
(2) Pearl: seawater or freshwater mollusks in the shell into small impurities in the body, the mantle will be secreted by stimulated a pearl quality (mainly calcium carbonate), it will be wrapped in layers of small impurities, has become a small beads, is the pearl. Pearl color is mainly white, pink and pale yellow, with a pearl luster, the surface faintly shining rainbow like iridescence pearl. Run the color white, bright light skin, fine round shape, the larger the value of the maximum size hard.
3 Turquoise: Turquoise is a self-colored gems, is a complete hydration of the copper and aluminum phosphate. Formula CuAl6 (PO4) 4 (OH) 8.5 H2O (five alkaline hydrated copper aluminum phosphate). Turquoise transparency as opaque, translucent sheet lower part. Polished glass surface is oil sheen, the fracture oil dim luster. Turquoise stone types including Bosi Song, the United States and Mexico, turquoise, turquoise, Egyptian turquoise and turquoise with a wire.
4 Lapis: Lapis Sodalite is a family of minerals; lapis lazuli of the formula (Na, Ca) 7-8 (Al, Si) 12 (O, S) 24 (SO4), Al2Cl2 · (OH ) 2 (OH) 2, which is often part of sodium for potassium replacement, is part of sulfur to sulfate, chloride, or the replacement of selenium. Lapis lazuli types including Persian, the Soviet Union lapis lazuli, or Spain, Chile, lapis lazuli.
5 Opal Stone: Opal is a mineral in the class, molecular formula SiO2 · nH2O (silica hydrate). As the opal in sio2 neatly arranged like a grating of small beads, like, when white light after diffraction in the above shot, scattered into the color spectrum, so the opal stone changes with eye-catching colors, especially red than those of the most valuable. Types, including white opal stone opal stone, black opal stone, crystal opal stone, fire opal stone, jelly opal stone opal stone or jade drops, boulder opal stone, opal stone gangue or matrix opal stone.
6 Olivine: Olivine is a self-colored gems, the general common colors are pure green, yellow-green to brownish green. Olivine is not colorless. Formula: (Mg, Fe) 2SiO4 (iron magnesium silicate). Types include peridot peridot, topaz, olivine, fayalite, "evening emerald" and boron magnesium stones.
7 Feldspar: Feldspar by mineralogical classification is divided into two main types: K-feldspar and plagioclase. Formula are: KAlSi3O8 (potassium aluminum silicate), NaAlSi3O8 (sodium silicate). Types include Moonstone feldspar or adularia, sand stone sun stone or feldspar, elongated stone, amazonite, or Amazon stone.
8 jade: jadeite (also known as Jade), soft jade. Jadeite is a silicate of sodium and aluminum, molecular formula: NaAl (SiO3) 2. Nephrite is a silicate of calcium and magnesium water, formula: CaMg5 (OH) 2 (Si4O11) 2.