Emerald has been one of the precious gems since ancient times. According to legend, 6000 years ago, someone in Babylon dedicated it to the Statue of Liberty. In ancient Babylon in the Persian Gulf, women especially like jade ornaments. Thousands of years ago, ancient Egypt and ancient Greeks also liked to make jewelry with emeralds. People in China also like jade. Emperors in Ming and Qing dynasties especially liked jadeite. Ming Chengzu regards it as precious as a golden cat's eye, and there is a saying that "the ceremonial crown needs a cat's eye jade". The jade belt of the Wanli emperor of the Ming Dynasty is inlaid with a very large emerald, which is now hidden in the Dingling Museum of the Ming Tombs. In addition to a large number of pearls and other precious stones, there are two emeralds weighing about 5 yuan.

Emerald is the birthstone of May, symbolizing luck and happiness. Wearing it will bring people a lifetime of peace. This is also the 55th wedding anniversary stone.

Emerald is a very old gem, which was used as jewelry in ancient Egypt. The color of emeralds is very charming. Some people use spinach green, onion heart green and tender tree bud green to describe it, but they can't accurately express its color. The green is a little yellow, but it seems a little blue, and even the spectrum seems to be a little less wavelength. Indeed, no natural color can make the eyes so comfortable. Whenever you stare at the green lawn and leaves, the pleasing feeling can be imagined, but it is not as good as the color of jade. It is one of the treasures that people can never get tired of seeing. Whether it is cloudy or sunny, whether it is under artificial light or natural light, it always emits soft and rich light. This is the charm of emerald, king of emeralds.

Emerald is a gem-grade green beryl. Its green color should reach a medium and rich green tone, that is, the color density should be saturated. Light green is usually called green beryl.

Beryllite is produced in nature, and its main component is Be3Al2[Si6O 18], which is a hexagonal beryllium aluminum silicate mineral. Emerald is formed because it contains a proper amount of Cr2O3(0. 15~0.6%). It is the most outstanding member of beryl family. This material belongs to high-grade gem.

Its color source is: a small amount of chromium oxide makes it appear crystal clear and beautiful green. Emerald is a silicate containing beryllium and aluminum, and its molecular formula is Be3Al2[Si6O 18], which belongs to the noblest member of beryl family. It belongs to hexagonal system. Crystal simplex is hexagonal column and hexagonal bipyramid, mostly rectangular column. Aggregates are granular, blocky, etc. Emerald green, glass luster, transparent to translucent. The refractive index is 1.564- 1.602, the birefringence is 0.005-0.009, and the polychromatic property is not obvious. Not an isotropic body. The hardness is 7.5 and the density is 2.63-2.90g/cm3. The cleavage is incomplete, and the shell breaks. Fragile. Under the irradiation of X-rays, emeralds emit very weak pure red fluorescence.