Name: Hypersthene (Mg,Fe+2)2Si2O6
Type: Mineral
Class: Silicate
Subclass: Inosilicate
Particle Size: Fine
Sample No.: hypersth_1
Owner: JHU
Wavelength Range: TIR
Origin: Western Greenland, via the Smithsonian (sample no. NMNHC2368).
Collection Date: N/A
Description: Black in color; a small amount of surface contamination was removed; some mineral inclusions were separated from the remainder of the sample after crushing.  Under the microscope, the sample was green-brown pleochroic, with a high index of refraction.  It appeared mildly altered with some (2%) iron-stained opaque material present. Particle size was Less than 2 micrometer. (Pyroxene Group) Original ASTER Spectral Library name was jhu.nicolet.mineral.silicate.inosilicate.powder.hypers1.spectrum.txt
Mineral:  Hypersthene (Mg,Fe+2)2Si2O6

Sample No.: hypersth.1

XRD Analysis:  Predominantly hypersthene with a small amount of 
talc and a small amount of some other mineral(s).  However, the 
amount of talc appears insufficient to affect the infrared spectrum, 
because even the strong hydroxyl bands of talc between 3600 and 
4600 cm-1, which should be prominent in the spectrum of the 0-74 
micrometers particle-size range, are not in evidence.

Chemistry:  Microprobe analysis indicated exsolution of a small 
amount of clinopyroxene, as shown by the presence of calcium and 
concomitant loss of magnesium and iron for 2 out of 20 analyses.  An 
average of all of the analyses:

SiO2	51.32
Al2O3	4.89
FeO	17.07
MgO	26.09
CaO	1.27
K2O	0.02
Na2O	0.05
TiO2	0.29
MnO	0.35
	_____
Total	101.33
