If a ruler perfectly observes the rites of the state, white jade will appear in the valley. But China is hardly the only culture to place a high value on jade. It is prized for its hardness, glassy luster, and rich translucent colors.
Colors vary from white to green, but there are also red, yellow and lavender jades.
In China, a clear emerald-green stone is valued most highly. According to ancient legend, yu, as the jewel is known, came from the holy mountains and was thought to be crystallized moonlight. In fact, jade came from along the Silk Road. Because jade is extremely hard, it might have been tried early on for tools and weapons. But jade is also brittle, and the forms that have survived appear to have been used for symbolic, rather than utilitarian purposes.