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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 HS180 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS180

MINERAL_TYPE: Cyclosilicate

MINERAL: Beryl

FORMULA: Be3Al2Si6O18

FORMULA_HTML: Be3Al2Si6O18

COLLECTION_LOCALITY: Maine

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Theoretical percentages of the oxides in the formula are BeO 14.0%, Al2O3 19.0%, SiO2 67.0%. The presence of alkalis (Na and K) and Li may considerably reduce the percentage of BeO. Small and variable amounts of zeolithic H2O are present.

Sieve interval 74-250µm.

"Results of petrographic examination: Hand sample is pale green and appears pure. Microscopic examination shows that there is a small amount (2% or less) of very fine, low birefringent material in the sample. The grains occasionally have rhombic or cubic shape. These grains are unidentifiable."

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Pure (Norma Vergo).

Pure beryl.

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 66.12 wt% SiO2
COMPOSITION: TiO2 0.01 wt% TiO2
COMPOSITION: Al2O3 17.36 wt% Al2O3
COMPOSITION: FeO 0.48 wt% FeO
COMPOSITION: MnO 0.00 wt% MnO
COMPOSITION: MgO 0.17 wt% MgO
COMPOSITION: CaO 0.01 wt% CaO
COMPOSITION: Na2O 0.35 wt% Na2O
COMPOSITION: K2O 0.03 wt% K2O
COMPOSITION: Total 84.53 wt%
COMPOSITION: O=Cl,F,S wt%
COMPOSITION: New Total wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

"Microprobe analysis shows that grains selected are homogeneous within and between grains. Average of 10 analyses lacking beryllium indicates silica and alumina content appropriate for beryl."

NOTE: EM composition total is the total without beryllium.

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

avg. grain size = 285µm

Conchoidally fractured beryl grains (spares yellow staining). Very pure 100% beryl. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_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 678 0.2-3.0µm 200 g.s.= 285 µm
LIB_SPECTRA: splib05a r 1331 0.2-3.0µm 200 g.s.=


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