Name: Diorite Gneiss
Type: rock
Class: Metamorphic
Subclass: Gneis
Particle Size: Coarse
Sample No.: gneiss7
Owner: JHU
Wavelength Range: All
Origin: Sample No. 464, The Hunt and Salisbury Collection at the U.S.Geological Survey, Denver, Co.
Collection Date: N/A
Description:  This is a coarse-grained sample composed of hornblende euhedra assocciated with biotite, with anhedra and subhedra of alkali feldspars (oligoclase and orthoclase)  which are slightly sericitized.  Zircon and pyrite crystals occur throughout the section.  There may be a trace of quartz present as well.  Some carbonate (?), or zircon masses (high relief, colorless, perhaps 3rd order B.R.) occur in this rock, often associated with the amphibole or opaques. Particle size was 500-1500 Micrometer. Original ASTER Spectral Library name was jhu.becknic.rock.metamorphic.gneiss.coarse.gneiss7.spectrum.txt
  Modes were 42.7% hornblende?, 29% oligoclase, 23.4% orthoclase, 1.74% 
biotite, 1.48%
zircon, 1.04% opaques, 0.87% calcite (else then 2.35% zircon).  
