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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: Dipyre BM1959,505 Scapolite DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: BM1959,505

MINERAL_TYPE: Tectosilicate

MINERAL: Dipyre (Scapolite group)

FORMULA: 3NaAlSi3O8*NaCl

FORMULA_HTML: 3NaAlSi3O8•NaCl

COLLECTION_LOCALITY: Unknown

ORIGINAL_DONOR: National Museum of Natural History

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Scapolites are metamorphic minerals with compositions suggestive of the feldspars. Dipyre is an intermediate composition of the solid solution series marialite-wernerite-meionite.

Two spectra are in the library, one of the original sample, and one after HL separation.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Scapolite + muscovite + 3.66, 3.36, 2.87, 2.838 Angstroms

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 56.8600 wt% SiO2
COMPOSITION: TiO2 0.00 wt% TiO2
COMPOSITION: Al2O3 22.8100 wt% Al2O3
COMPOSITION: FeO 0.0660 wt% FeO
COMPOSITION: MnO 0.0100 wt% MnO
COMPOSITION: MgO 0.0100 wt% MgO
COMPOSITION: CaO 6.5780 wt% CaO
COMPOSITION: Na2O 9.7040 wt% Na2O
COMPOSITION: K2O 1.4000 wt% K2O
COMPOSITION: Cl 3.8920 wt% Cl
COMPOSITION: F 0.0220 wt% F
COMPOSITION: SO3 0.0100 wt% SO3
COMPOSITION: CO2 0.1000 wt% CO2
COMPOSITION: Total 101.4620 wt%
COMPOSITION: O=Cl,F,S .8875 wt% #correction for Cl, F, S
COMPOSITION: New Total 101.5745 wt%

COMPOSITION_TRACE:

None

COMPOSITION_DISCUSSION:

1. Mol % SiO2 includes .0196 mol % SiF4.
Mol % SiO2 includes 1.8555 mol % SiCl2.
2. Fe oxide in analysis is total Fe+2 + Fe+3.
3. Number of tetrahedral sites per formula set at 12.
4. Number of anions per formula unit = 25.03625.
5. Cation site assignments: Standard clay-mineral default with changes.
Must occupy tetrahedral sites: Si Al
To big cation sites: Fe+2 Mn Mg

XMe = 25.70 % Me

XMe = Ca/(Ca+Na) = 27.2 % Me

Sample: Dipyre

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Not done yet

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1c2_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 1451 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 2441 0.2-3.0µm 200 g.s.=


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