Name: Hornblende Ca2(Fe+2,Mg)4Al(Si7Al)O22(OH,F)2
Type: Mineral
Class: Silicate
Subclass: Inosilicate
Particle Size: solid
Sample No.: hornblen_3
Owner: JHU
Wavelength Range: TIR
Origin: Calumet Island, Ottowa River, Canada via the Smithsaonian(sample no. NMNH 78662)
Collection Date: N/A
Description: Sample was a cluster of several large, deep green crystals. A small amount of contamination was found in thin veins along cleavage planes. Microscopic examination revealed newr purity with less than 1% impurities of low index veins. An index of refraction of <1.64 and pleochroism (green to greenish brown) indicated that this is probably magnesian hornblende. Sample had cleavage face. (Amphibole Group) Original ASTER Spectral Library name was jhu.nicolet.mineral.silicate.inosilicate.solid.hornbl3.spectrum.txt
Mineral:  Hornblende Ca2(Fe+2,Mg)4Al(Si7Al)O22(OH,F)2

Sample No.: hornblen.3

XRD Analyis:  Pure magnesiohornblende

Chemistry:  Microprobe analysis shows a slight variation in alumina 
(0.5% to 2.5%) which is, oddly enough, offset by inverse variation in 
magnesia. With that minor exception, the sample appears 
homogeneous and typical magnesiohornblende. Average of 15 
analyses:

SiO2	56.14
Al203	1.24
FeO	6.46
MgO	20.90
CaO	13.17
K2O	0.12
Na2O	0.32
TiO2	0.04
MnO	0.18
	_____
Total	*98.55
	*OH and F not measured.
