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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: Montmorillonite+Illite CM37 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: CM37

MIXTURE_TYPE: Intimate

MIXTURE: Montmorillonite + Illite (Metabentonite) (Montmorillonite group)

FORMULA: (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2*nH20 + (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

FORMULA_HTML: (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2•nH2O + (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

COLLECTION_LOCALITY: Strasburg, Virginia

ORIGINAL_DONOR: Clay Mineral Standard, Wards Natural Science Inc

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Sample is tan in color.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Analysis by Norma Vergo indicates the sample is clay + quartz + calcite + trace feldspar? The less than 2µm cut has illite/smectite 96%, illite + trace amounts of quartz.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: XRF # XRF, EPMA, ICP(Trace), WChem


COMPOSITION
KEYWORD		 Oxide
ASCII		 Amount Weight
Percent, %		 Oxide
html
COMPOSITION: SiO2 46.5 wt% SiO2
COMPOSITION: TiO2 1.05 wt% TiO2
COMPOSITION: Al2O3 22.7 wt% Al2O3
COMPOSITION: Fe2O3 3.19 wt% Fe2O3
COMPOSITION: FeO 0.29 wt% FeO
COMPOSITION: MnO less than 0.02 wt% MnO
COMPOSITION: MgO 2.74 wt% MgO
COMPOSITION: CaO 5.86 wt% CaO
COMPOSITION: Na2O 0.31 wt% Na2O
COMPOSITION: K2O 5.92 wt% K2O
COMPOSITION: P2O5 0.12 wt% P2O5
COMPOSITION: H2O+ 6.18 wt% H2O+
COMPOSITION: H2O- 1.52 wt% H2O-
COMPOSITION: H2O 7.70 wt% H2O
COMPOSITION: LOI 11.2 wt% LOI
COMPOSITION: Total 99.61 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

XRF Analysis by Branch of Analytical Chemistry, USGS, Denver. Total above includes LOI value rather than H2O values, and does not include value for FeO as it was determined at same time as H2O. Trace analysis was performed and will be added later.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

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