Spodumene - LiAlSi2O6

Spodumene was first described in 1800 for an occurrence in the type locality in Uto, Sodermanland, Sweden. It was discovered by Brazilian naturalist Jose Bonifacio de Andrada e Silva. The name is derived from the Greek spodumenos, meaning burnt to ashes, owing to the opaque, ash-grey appearance of material refined for use in industry. In the historical literature, the mineral is often referred to as "triphane".

Spodumene is a pyroxene mineral that is found, almost exclusively, in granite pegmatites. It has a chemical composition of LiAlSi2O6 but small amounts of sodium sometimes substitute for lithium and only one minor substitution of Al by Fe3+. It is worked as an ore of lithium, but it is most highly prized as a gem material; the varieties kunzite (pink) and hiddenite (green) are especially sought after. It is usually found as a constituent of lithium-rich pegmatites. Single crystals of 14.3 m (47 ft) in size are reported from Etta Mine in the Black Hills of South Dakota, United States. Spodumene is a characteristic mineral of the lithium-rich granitic pegmatites in which it is usually restricted to the more central parts of the pegmatite, and commonly associated with quartz, petalite, albite, lepidolite and beryl.

Optical properties:
Habit: Most often as long, flat, prismatic crystals. Also as rectangular crystals, tabular, bladed, as elongated crystals.
Color: Colorless.
Relief: High.
Birefringence: High, II-III order.

etta5.jpg

Metric crystal of spodumene, Etta mine (USA). image from Dr. Thomas Krassmann.



spodumene.jpg

Spodumene crystal (kunzite). Photo by Gery Parent




Bibliography



• Cox et al. (1979): The Interpretation of Igneous Rocks, George Allen and Unwin, London.
• Howie, R. A., Zussman, J., & Deer, W. (1992). An introduction to the rock-forming minerals (p. 696). Longman.
• Le Maitre, R. W., Streckeisen, A., Zanettin, B., Le Bas, M. J., Bonin, B., Bateman, P., & Lameyre, J. (2002). Igneous rocks. A classification and glossary of terms, 2. Cambridge University Press.
• Middlemost, E. A. (1986). Magmas and magmatic rocks: an introduction to igneous petrology.
• Shelley, D. (1993). Igneous and metamorphic rocks under the microscope: classification, textures, microstructures and mineral preferred-orientations.
• Vernon, R. H. & Clarke, G. L. (2008): Principles of Metamorphic Petrology. Cambridge University Press.


Photo
spodumene(2).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(4).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(5).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(6).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(7).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(8).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 1x (Field of view = 9mm)
spodumene(9).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(11).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(12).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(14).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(15).jpg

Spodumene (high relief and colorless) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. PPL image, 2x (Field of view = 7mm)
spodumene(16).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(17).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(19).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(20).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(21).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(24).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(25).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(26).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(28).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(29).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(21).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(24).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(25).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(32).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(34).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(35).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(37).jpg

Spodumene (high relief and colorless) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. PPL image, 2x (Field of view = 7mm)
spodumene(38).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(40).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 2x (Field of view = 7mm)
spodumene(42).jpg

Spodumene (high relief and colorless) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. PPL image, 10x (Field of view = 2mm)
spodumene(43).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(44).jpg

Spodumene (high relief and colorless) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. PPL image, 10x (Field of view = 2mm)
spodumene(45).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(48).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(50).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(54).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(55).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)
spodumene(57).jpg

Spodumene (high interference colors) and plagioclase in a pegmatite from Bikita, Zimbawe, Africa. XPL image, 10x (Field of view = 2mm)