Name: Topaz Al2SiO4(F,OH)2
Type: Mineral
Class: Silicate
Subclass: Nesosilicate
Particle Size: Solid
Sample No.: topaz_1
Owner: JHU
Wavelength Range: TIR
Origin: Rhondonia, Brazil via Don Hoover, USGS
Collection Date: N/A
Description: The sample was a 1 cm x 1 cm x 1 cm fragment of a single crystal.  It was colorless and appeared free of fluid inclusions under the microscope (however, the presence of a CO2 band at 4.3 micrometers in the infrared reflectance spectra of particulate samples shows that fluid inclusions are present). Sample was cleavage face.(Isolated tetrahedra) Original ASTER Spectral Library name was jhu.nicolet.mineral.silicate.nesosilicate.solid.topaz1.spectrum.txt
Mineral:  Topaz Al2SiO4(F,OH)2

Sample No.:  topaz.1

XRD Analysis:  Pure topaz.

Chemistry:   Microprobe analysis by Lou Walter and volatile analysis 
by C. S. Papp, J. D. Sharkey, and K. J. Curry and XRF analysis of the 
non-volatiles by J. Taggare, A. Bartel, , USGS Branch of Analytical 
Chemistry, Denver.  Ten microprobe analyses indicate homogeneity 
within and among grains, and the composition agrees with that of 
topaz.  Average of 10 analyses:

SiO2	36.50
Al2O3	62.50
FeO	<0.05
MgO	0.15
CaO	<0.02
K2O	<0.02
Na2O	<0.17
TiO2	<0.02
MnO	<0.02
P2O5	<0.06
H2O	0.15
CO2	<0.01
F	0.10
	_____
Total	99.77
