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Chemical composition LiAl(SiO3)2
Crystal system Monoclinic
Habit Prismatic, tabular
Cleavage Perfect, prismatic
Fracture Uneven
Hardness 7
Optic nature Biaxial +
Refractive index 1.66-1.68
Birefringence 0.015
Dispersion Low, 0.017
Specific gravity 3.18
Lustre Vitreous
Pleochroism Strong
Faceted Yellow Hiddenite
Photo courtesy of
Wild Fish Gems

Spodumene image gallery


Crystal system: monoclinic.
Habit: flattened and corroded prism with vertical striations, irregular capping reminiscent of Mountain range; sometimes massive. Generally long slender prismatic crystals, often etched.

Chemical composition

Lithium Aluminium Silicate (LiAl(SiO3)2).
Generally there is little Na present. Fe, Ca may replace Li; Cr may be present (Hiddenite green)


Color and varieties

Hiddenite: yellow green to emerald green (due to Cr).
Kunzite: clear lilac, pink, violetish, purplish (due to Mn).
Other (Spodumene): Yellow, colourless, gray, blue (yellows due to Fe).


Complex three phase inclusions characteristic of of spodumene; cleavages; growth tubes; needle like etch tubes; twin planes; crystals.


Very strong fuorescence: golden pink to orange under LWUV and weaker under SWUV.
Sometimes phosphorescent.


There is generally a strong absorption along the c-axis.

Specific gravity

Spodumene sinks in heavy liquid 2.88


  • Irradiation (colorless to pink,other colors).
  • Heat treatment (green purple or pink to lighter).


Name Key seperations
Euclase Slightly lower S.G., UV fluorescence
Sillimanite Inclusions, generally inert under UV, higher birefringence
Tourmaline S.G. (lower heft), uniaxial character, Inclusions, R.I and D.R.
Thulite Higher S.G., higher R.I. range and UV fluorescence
Rose Quartz Lower S.G, R.I.
Natural Spinel Singly refractive nature, magnification, spectrum

Name Key seperations
Emerald Lower heft (floats in 2.88), uniaxial, R.I, D.R., magnification features
Chrysoberyl Higher S.G. (heft), spectrum, R.I.
Diopside Higher S.G., R.I., spectrum and stronger doubling of Back facet edges or inclusions

Name Key seperations
Amethyst Lower S.G. (floats 2.88), UV reaction unlike spodumene, bull's-eye optic figure, R.I.
Morganite Lower S.G. (floats 2.88), uniaxial, R.I., magnification features
Topaz Higher heft, low birefringence and UV reaction unlike spodumene
Pink sapphire Higher heft, R.I higher and lower birefringence


Geological occurrence: Spodumene occurs in granite pegmatites, sometimes with very great sizes.

Geographical occurrence: Mainly North and South America; Madagascar; Burma; Brazil. USA: N.Carolina (yellowish green)- hiddenite; Connectiuit (lilac); CA (Kunzite); Coahulia Mountains (yellow, yellowish green, blusih pink) Madagascar: Kunzite, green, yellowish - Anjanabonoina. Brazil: Paler hiddenite, white spodumene, cat's eye, yellow to pale greeen, bluish pink Kunzite, yellow and green Burma: Spodumene from upper Mogok stone tract (blue) Afghanistan: Kunzite, yellow, blue and green.