Name: Granite
Type: rock
Class: Igneous
Subclass: Felsic
Particle Size: Fine
Sample No.: Granite_H5
Owner: JHU
Wavelength Range: All
Origin: From Santa Rita Mountains, Arizona via Smithsonian (Cat No.NMNH 113640-15)
Collection Date: N/A
Description: Powder derived from a pinkish medium-grained sample consisting of feldspar and quartz with minor biotite. Some areas of the sample show granophyric texture, and a few vugs are present.Particle size was 0-75 micrometers. Original ASTER Spectral Library name was jhu.becknic.rock.igneous.felsic.fine.granit5.spectrum.txt
Composition:

Petrographic Description:  The sample consists of 47.9% orthoclase, 35.2% 
quartz, 14.6% plagioclase (of which 6.6% is perthitic), 1.4% biotite and 
0.8% magnetite.  In these rocks the quartz anhedra show moderate to strong 
undulatory extinction, the orthoclase anhedra are often finely perthitic and 
slightly kaolinitized.  The plagioclase often show sericitic alteration while 
the biotite may be altered to chlorite.  The thin section did not show any 
carbonate, but the spectrum and chemical analysis both indicate a trace is 
present.

Microprobe Analysis:  In this sample all the plagioclase probed was pure 
albite.

Chemical Analysis:
SiO2  75.10
CaO  0.19
TiO2  0.18
Na2O  3.6
Al2O3  13.0
K2O  5.5
Fe2O3  1.3
H2O  0.73
FeO  0.18
P2O5  0.01
MnO  0.02
CO2  0.05
MgO  0.05
TOTAL  99.91
