(repeating unit)
IMA symbolElb[1]
Strunz classification9.CK.05
Crystal systemTrigonal
Crystal classDitrigonal pyramidal (3m)
H–M symbol: (3m)
Space groupR3m
ColorGreen, red to pink, blue, orange, yellow, colorless, multicolored
Crystal habitPrismatic; striated
CleavagePoor/indistinct on {1120} and {1011}
Mohs scale hardness7+12
DiaphaneityTransparent to opaque
Optical propertiesUniaxial (−); moderate relief
Refractive indexnω = 1.635–1.650, nε = 1.615–1.632
Birefringenceδ = 0.020
Other characteristicspiezoelectric and pyroelectric
Major varieties
Rubellitered to pink

Elbaite, a sodium, lithium, aluminium boro-silicate, with the chemical composition Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4,[4] is a mineral species belonging to the six-member ring cyclosilicate tourmaline group.

Elbaite forms three series, with dravite, with fluor-liddicoatite, and with schorl. Due to these series, specimens with the ideal endmember formula are not found occurring naturally.

As a gemstone, elbaite is a desirable member of the tourmaline group because of the variety and depth of its colours and quality of the crystals. Originally discovered on the island of Elba, Italy in 1913, it has since been found in many parts of the world. In 1994, a major locality was discovered in Canada, at O'Grady Lakes in the Yukon.

Elbaite forms in igneous and metamorphic rocks and veins in association with lepidolite, microcline, and spodumene in granite pegmatites; with andalusite and biotite in schist; and with molybdenite and cassiterite in massive hydrothermal replacement deposits.

Elbaite is allochromatic, meaning trace amounts of impurities can tint crystals, and it can be strongly pleochroic. Every color of the rainbow may be represented by elbaite, some exhibiting multicolor zonation. Microscopic acicular inclusions in some elbaite crystals show the cat's eye effect in polished cabochons.

Elbaite varieties

Elbaite specimen at Yale's Peabody Museum of Natural History

See also


  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ Elbaite. Mindat
  3. ^ Elbaite. Webmineral
  4. ^ "IMA Mineral List with Database of Mineral Properties".