zone fluids in association with serpentinite. Jadeitite is resistant to weathering, and alluvial boulders of jadeitite released from the serpentine-rich environments in which they formed can have weights of up to tons. Raw specimens having Burmese tax stamps or polished slots for evaluating quality are prized by some collectors. Colors Jadeite's color commonly ranges from white through pale apple green to deep jade green but can also be blue-green (like the recently rediscovered "Olmec Blue" jade), pink, lavender and a multitude of other rare colors. Chloromelanite is a very dark green to black variety. Color is largely affected by the presence of trace elements such as chromium and iron. Its translucence varies from opaque to almost clear. Variations in color and translucence are often found even within a single specimen. Occurrence Significant occurrences of jadeite are isolated and rare. It is found exclusively in high-pressure, low-temperature metamorphic rock of continental margins. Here it may be found as pods or veins or as disseminated grains. Deposits are found in Myanmar, the Alps, Russia, California, Japan, and Guatemala. In the Franciscan Complex of California, jadeite is associated with glaucophane, aragonite, muscovite, lawsonite, and quartz. However, occurrences of lapidary quality are almost exclusive to Myanmar. Stream boulders of the Uyu River remain an important source of jadeite. Uses Jadeite is the dominant mineral of the most desirable variety of jade. This was prized in traditional Chinese culture, where it was worked into a great variety of beautiful ornaments and utensils. Jadeite was also used by Stone Age peoples for implements and weapons. Jade received its name, "piedra de ijada" ("stone of the side"), because it was once thought to cure kidney ailments when applied to the side of the body. Jade Jadeite is one of two minerals recognized as the gemstone jade. The other is nephrite. Occasionally, other minerals such as serpentine or quartz are sold as jade, but the difference can be determined by cleavage and hardness. Jadeite jade is the most valuable form, with the highest-quality material commanding prices well in excess of $200 per carat . Jadeite jade first came into significant use in China only towards the end of the 18th century, as fei tsui. Jadeite from the Motagua Valley, Guatemala, was used by the Olmec and Maya peoples, as well as the indigenous peoples of Costa Rica. Unusual colors, like "Olmec blue" jade, which is characterized by its