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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Beryl GDS9 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS9

MINERAL_TYPE: Cyclosilicate

MINERAL: Beryl

FORMULA: Be3Al2Si6O18

FORMULA_HTML: Be3Al2Si6O18

COLLECTION_LOCALITY: Maine, USA

ORIGINAL_DONOR: Wards Natural Science Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

None

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Beryl + trace other (Norma Vergo).

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Bimodal grains size distribution:

population 1 140µm 97 vol%
population 2 15µm 3 vol%

avg. grain size of populations = 138µm

Conchoidally fractured grains, trace of opaque material, length fast, uniaxial (-). Smaller grains slightly adhere to larger grains. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 666 0.2-3.0µm 200 g.s.= 138 µm
LIB_SPECTRA: splib05a r 1318 0.2-3.0µm 200 g.s.=


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