I once held a six-inch cube of the finest jade in my hands. Nothing more than a simple
cube, yet it was extraordinarily beautiful. It was a dark and lustrous green that drew the eye, to the touch the surface felt smooth and almost oily. Beyond it’s beauty the most noticeable thing about jade was its weight. It was very, very heavy.
Jade is an opaque gemstone that ranges in color from dark green to almost white. The minerals jadeite and nephrite are both considered jade, with jadeite being the more valued form.
Jadeite is a silicate of sodium and aluminium, NaAl(SiO3)2, often also containing some iron, calcium, and magnesium. Jadeite is one of a group of minerals called pyroxenes. Jadeite does crystalize as a monoclinic crystal, but is seldom found in this form. It generally occurrs as a compact aggregate. Jade is extremely tough, hard (6.5 – 7 on the Moh's scale), and difficult to break. Jadeite is found in eastern Asia, Burma, Tibet and southern China.
Nephrite, is a silicate of calcium and magnesium, it also contains small amounts of iron. It has a hardness of 6 to 6.5, and is found in Alaska, Mexico, New Zealand, Siberia, and Turkestan.
The Chinese and Japanese consider jade the most precious of all stones. Jade carvings dating from the Neolithic have been found in China. Jade items from the Shang dynasty include the pi, (a round disk), the kuei, (an ax), and the tsung, (a cylinder). Jade, because of its toughness, is carved by abrasion, and until the development of the iron drill during Anyang era of the Shang dynasty simple forms predominated. After this time jade carvings become ever more intricate.