Hsianghualite

Hsianghualite is a tectosilicate (framework silicate) of lithium, calcium and beryllium, with fluorine, a member of the zeolite group. It was discovered in 1958 and named for the type locality, Hsiang Hua, 香花, meaning fragrant flower.

Hsianghualite
Hsianghualite from the type locality. Specimen size 1.5 cm
General
Category	Zeolite
Formula (repeating unit)	Li2Ca3(BeSiO4)3F2
Strunz classification	9.GB.05 (10 ed) 8/J.16-10 (8 ed)
Dana classification	77.1.1.5
Crystal system	Isometric
Crystal class	Tetartoidal (23) H-M symbol: (23)
Space group	I213,[1] originally reported as 4 3 2[2]
Identification
Formula mass	475.4 g/mol
Color	White or colorless
Crystal habit	trisoctahedral or dodecahedral crystals or granular masses[2]
Cleavage	None
Tenacity	Brittle[3]
Mohs scale hardness	6.5
Luster	Vitreous
Streak	White
Diaphaneity	Transparent to translucent
Specific gravity	2.97 to 3.00, measured[4]
Refractive index	n = 1.6132[2]

StructureEdit

Structure is analogous to that of analcime with Be and Si in tetrahedral co-ordination forming a three-dimensional framework.^[1] Its space group is I2₁3^[1] (Previously reported as I4₁32^[2]). Unit cell parameters are a = 12.879 or 12.897,^[2][4] and Z = 8.

EnvironmentEdit

It occurs within phlogopite veins in the light-coloured band of green and white banded metamorphosed Devonian limestone which has been intruded by beryllium-bearing granite.^[5] Associated mineral include fluorite, liberite, chrysoberyl, taaffeite and nigerite.^[1]

LocalitiesEdit

Hsianghualite has been found only at the type locality, the Xianghualing Mine in Linwu County, Hunan Province, China.

This article uses material from the Wikipedia article  Metasyntactic variable, which is released under the  Creative Commons Attribution-ShareAlike 3.0 Unported License