Saturday, May 14, 2011

JADE

Well how do you like these little apples??  Where else would you find them but in the Annapolis Valley of  Nova Scotia, Canada?  I got them on a wonderful fall trip in 1997 and wanted to share this history of jade that I found.  The reason I went on this search because very recently someone told me that jade was only found in Canada which I knew was a bag of baloney!  We are famous for a lot of great and wonderful things but being the world's only supplier of jade is not one of them!!
Jade dragon
Western Han Dynasty (202 BC-9 AD

The English word jade (alternative spellings "jaid", "jadeite") is derived (via French l'ejade and Latin ilia) from the Spanish term piedra de ijada (first recorded in 1565) or "loin stone", from its reputed efficacy in curing ailments of the loins and kidneys. Nephrite is derived from lapis nephriticus, the Latin version of the Spanish piedra de ijada.

Nephrite versus jadeite

Nephrite and jadeite were used from prehistoric periods for hardstone carving. Jadeite has about the same hardness as quartz, while nephrite is somewhat softer. Both nephrite and jadeite are tough, but jadeite is tougher than nephrite.  It was not until the 19th century that a French mineralogist determined that "jade" was in fact two different materials. The trade name jadite (not to be confused with jadeite) is sometimes used for translucent or opaque green glass.
Among the earliest known jade artifacts excavated from prehistoric sites are simple ornaments with bead, button, and tubular shapes.  Additionally, jade was used for axe heads, knives, and other weapons, which can be delicately shaped. As metal-working technologies became available, the beauty of jade made it valuable for ornaments and decorative objects. Jadeite measures between 6.5 and 7.0 Mohs hardness, and Nephrite between 5.5 and 6.0, so it can be worked with quartz or garnet sand, and polished with bamboo or even ground jade.

Unusual varieties

Nephrite can be found in a creamy white form (known in China as "mutton fat" jade) as well as in a variety of green colours, whereas jadeite shows more colour variations, including blue, lavender-mauve, pink, and emerald-green colours. Of the two, jadeite is rarer, documented in fewer than 12 places worldwide. Translucent emerald-green jadeite is the most prized variety, both historically and today. As "quetzal" jade, bright green jadeite from Guatemala was treasured by Mesoamerican cultures, and as "kingfisher" jade, vivid green rocks from Burma became the preferred stone of post-1800 Chinese imperial scholars and rulers. Burma (Myanmar) and Guatemala are the principal sources of modern gem jadeite, and Canada of modern lapidary nephrite. Nephrite jade was used mostly in pre-1800 China as well as in New Zealand, the Pacific Coast and Atlantic Coasts of North America, Neolithic Europe, and south-east Asia. In addition to Mesoamerica, jadeite was used by Neolithic Japanese and European cultures.

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