Amazonite

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Refractive Index : 1.530 – 1.522 (+0.004 – 0.004)

Optical Characteristic : DR Biaxial negative , usually AGG reaction

Specific Gravity : 2.56 (+ 0.02 – 0.02)

Formula : KAlSi3O8

Crystal System : Triclinic

Variety/Species : Microcline Feldspar

Species/Group : Feldspar Group

Birefringence : 0.008

Dispersion : None

Hardness : 6 to 6.5

Toughness : Poor

Ultrasonic : Never

Steam : Never

UV Long : Inert to weak yellowish green

UV Short : Inert

Pleochroism : None

Strength : N/A

Pleochroism Colors : None

Heat : Avoid heating

Acids : Attacked by acids and/or chemicals

Light : Stable

Polish Luster : Vitreous to greasy

Fracture : Uneven to splintery

Fracture Luster : Vitreous to pearly

Clarity Type : N/A

Tones : N/A

Saturations : N/A

Cause of Color : Lead and water color centers

Enhancements : Wax impregnation – This hides the cleavage cracks that break the surface. It can be detected through hot point test and infrared spectroscopy. This treatment is moderately stable.Irradiation – This treatment produces blue amazonite from white amazonite and is usually not detectable. It is very stable.

Cleavage : Perfect and easy in 2 directions.

Color Range : Light green, green, greenish blue, white, orange, pink, pinkish, orany, greenish, bluish, whitish sometimes light orange to pink

Transparency : Semitranslucent to opaque

Phenomena : Aventurescence, (rare), Schiller effect

Separations : Amazonite from-
Chalcedony: RI, appearance, fracture/cleavage, SG (possibly). Turquoise: RI, appearance, spectrum. Aventurine quartz: RI, appearance, fracture/cleavage, SG.

Identifying Characteristics and information
Dyed green and dyed blue amazonite gemstones appear red or pinkish through a chelsea filter.Occasionally has a faint sheen.Spot RI is usually 1.522 – 1.530 ( +/-.004)

Spectral Data
Not Diagnostic.

Trade Names and Misnomers
Amazon jade (M)
Amazon Stone
Amazonite
Colorado jade (M)
Pike’s Peak jade (M)

Sources Brazil, Madagascar, Norway, US, USSR.

Tags: amaznoite, amazon jade, amazon stone, colorado, microcline feldspar, pikes jade