Class: Silicates
Group: Pyroxene
Original description: Damour, A. A., 1863. Notice et analyse sur le jade vert. Réunion de cette matière minérale à la famille des Wernerites — Comptes Rendus Hebdomadaires des Séances de l’Académie des Sciences 56: 861—865 [
view in ‘Library’].
Type locality: Myanmar.
Type material: unknown.
Etymology: from jade, a material commonly containing jadeite.
Distribution: Guatemala: in the Motagua Valley, near the Sierra de las Minas; Japan; Myanmar: Kachin; Russia: around Lake Baikal, Siberia; USA: California, San Benito (
Anthony et al., 2001—2005).
Chemistry
NaAlSi2O6
Essential elements: oxygen (O), sodium (Na), aluminium (Al), silicon (Si).
Crystal data
Crystallography: monoclinic — prismatic.
Crystal habit: crystals rare, prismatic with {110}, {111}, and {100} as dominant forms; commonly massive, or fibrous, granular, compact.
Twinning: single and lamellar on {100} and {001} (
Anthony et al., 2001—2005).
Optical properties
Colour: apple-green, emerald-green, bluish green, greenish white, white, may show green spots, rarely blue or violet; colourless in thin section (
Anthony et al., 2001—2005).
Diaphaneity: translucent (
Anthony et al., 2001—2005).
Lustre: vitreous (
Arem, 1987: 117).
Refractive index: 1.652—1.688 — anisotropic [biaxial (+)] (
Lazzarelli, 2012).
Birefringence: 0.012—0.02.
Dispersion: none.
Pleochroism: none (
Arem, 1987: 117).
Material from ‘Repository’