Jadeite (NaAISi206)

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Jadeite (NaAISi206)

 

Silicate of sodium and aluminium. Jadeite is a member of the alkaline

pyroxene group of minerals because its the source of one of the

ornamental materials commonly known as jade, a word possibly derived

from the Spanish "ijada", or "flank", due to its alleged therapeutic

action on diseases of the kidneys.

 

Crystal system: Monoclinic

 

Appearance: Occurs as granular aggregates of small crystals but at

times found in crystals of a few centimeters. Color can vary a great

deal due to mimimal differences in composition. As far as I heard to

date, colors can be off-white, grayish white, brown, yellow-brown,

orange-yellow, reddish orange, lilac, blue-gray or various shades of

gray and green.

 

Physical properties: Hardness of 6.5-7 with extraordinary tenacity (the

opposite of brittleness) for a mineral, especially one where tiny

individual crystals sometimes display apparent cleavage traces. Density

varies from approx 3.30 to 3.36 g/cm3 but usually its 3.34 g/cm3.

 

Very dark green variety can be around 3.40 g/cm3. Massive material used

for ornamental purposes usually gives one index around 1.66.

 

Genesis: Formed by regional metamorphism and occurs in lenticular

masses or veins. Also found as alluvial pebbles and boulders.

 

Where from? : Mainly from northern Burma where its recovered from rock

rather than alluvium. Very tiny quantities found in Japan, Tibet,

U.S.A. (California), possibly Canada too and Guatemala. Also found as

small crystals in Swiss Alps (some of a few centimeters).

 

P.S. -- Next subject "Jadeite Jade" coming soon.