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USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Dipyre BM1959-505.HLsp 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.

IMAGE_OF_SAMPLE:
NO PHOTO

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

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

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: EM # XRF, EPMA, 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