Jadeite is a pyroxene mineral and one of the two types of pure jade. The other is known as nephrite. Jadeite is the rarer of the two, and as a result it is more precious. The most valuable form of jadeite is a striking and even emerald green known as "imperial jadeite". The history of jadeite goes back several thousand years when it was first used to make weapons and tools because of its toughness. Jadeite was highly prized by the Mayans and Aztecs, in fact the name "jade" originates from the Spanish "piedra de ijada", meaning "stone for the pain in the side". It was thus named after Spanish explorers noticed natives of Central America holding pieces of jade to their sides to cure ills. In Chinese, jade is known as "yu", which means "heavenly" or "imperial". Therefore, it is considered to be the imperial gem in Chinese culture. In China,jade was found in the tombs of Shang kings.
Minerals and precious stones: Earth’s jewels
Most minerals on Earth are formed when magma rises from the depths of the planet to the surface and then cools. Crystals form from chemical elements present in the liquid rock, somewhat like the way rain turns into snow crystals in the cold. Over time, the structure of some minerals changes under high pressure or high temperatures, producing new kinds of minerals in the process. More than 3,500 different minerals have been discovered so far. Most of them combine to form rocks, like the quartz, feldspar, and mica found in granite. The rarest and most beautiful may be turned into jewelry. This family of minerals, called gems, groups together some 50 different semiprecious stones, including agate, opal, and jade, and four precious stones. These most highly prized gems are diamond, ruby, sapphire, and emerald.