Gerald Lee Bowiin, age 13, of Bay City, Texas, for his question:
What mineral is jade?
Gerald purchased a sample of nephrite for his rock collection. The cans told that this mineral is jade. Later he was given a sample of jadite, cihich also was said to be jade. nephrite and jadeite are different minerals and when both are represented as real jade, one suspects hanky pantry. But both of these minerals are qualified to be called jade.
In olden days, people believed certain precious and semi precious stones brought good luck of bad luck. Others mere said to cure this or that disease or to ward off whatever plagues might be striking the neighbors. For example, the Spanish trusted a certain smooth green mineral to cure a pain in the side. They named it piedra de ijada meaning "stone of the side". We call it jade.
Several different minerals are called jade, though none can be trusted to ease a pain in the side. Their outstanding qualities are beauty of color and texture. Since ancient times, the jades have been treasured as carving stones. The best qualities give off a musical resonance and a precious jade carving of the Orient often stands beside a small hammer. When an admiring visitor has feasted his eyes, he taps,the work of art and enjoys a soft sound that echoes like a fairy gong.
In ancient China, precious treasures mere carved from nephrite jade. Its gentle colors range through waxy greens and browns, soft yellows, off white and almost black. The mineral nephrite is a silicate with calcium, magnesium and iron. Samples vary and the jade quality depends on color and texture. Our local rock store samples usually come from California or Wyoming, Alaska or British Columbia.
Jadeite jade is a harder, denser mineral than nephrite jade and its colors are deeper and more lustrous. Jadeite is a silicate mineral, with molecules of silicon and oxygen. It also contains sodium and aluminum. As in nephrite, the waxy jade type colors are donated by traces of impurities in the basic mineral.
A trained expert may hesitate to distinguish between samples of nephrite and jadeite by merely looking. But simple lab tests prove which is which. Also, the price tag states the difference in practical terms. Samples of nephrite jade may range from $2.00 to $200.00 per pound, depending mainly on color and texture. But top quality jadeite jade is far more valuable.
When tested for mineral identification, jadeite fuses easily and fortes a bubbly white glassy material. Because of its sodium content, the flame lox is with yellow. 2dephrite fuses less easily, minus the frothy bubbles and the yellow tint in the flame. Tinted serpentine, idocrase, hessonite and a long, list of other minerals may be called jade. Tests prove them to be less hard and less dense than jadeite jade.