Sample Description USGS Spectral Library Version 7

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
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TITLE: Clinochlore GDS159 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS159

MINERAL_TYPE: Phyllosilicate

MINERAL: Clinochlore, Chlorite

FORMULA: (Mg,Fe2+)5Al((Si3Al)O10(OH)8

FORMULA_HTML: (Mg,Fe²⁺)₅Al(Si₃Al)O₁₀(OH)₈

COLLECTION_LOCALITY: Frisco Mine, California? ORIGINAL_DONOR: Jim Post CURRENT_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory. ULTIMATE_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory. SAMPLE_DESCRIPTION:

Clinochlore was previously called Sheridanite.

IMAGE_OF_SAMPLE:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS: 40 kV - 30 mA, 6.5-9.5 keV (sheridan.out=sherd9.out) Reference: JCPDS #12-242 Found: Chlorite type IIb; weak but sharp reflection at 9.3 degrees 2 theta; (mica?); weak reflection at 3.13 Angstroms (albite?) Sought but not found: quartz Comments: An excellent chlorite pattern; sharp reflections indicate good crystallinity. The chemical analysis is that of a clinochlore. J.S. Huebner, J. Pickrell, and T. Schaefer, 1994, written communication. 40 kV - 30 mA, 6.5-9.5 keV File: sherd159.out, -.mdi (smear mount on quartz plate) References: Bailey (1988 in Clays and Clay Minerals 36, 193-213); JCPDS #25-177, 35-731, 21-1276; Huebner's reference patterns Found: Clinoclore type IIbb, weak reflection at 9.4 Angstroms (mica?), 3.24 Angstroms (sphene(?), 3.12 Angstroms (La-monazite?) Comment: Very sharp reflections indicate high degree of crystallinity and compositional homogeneity. Position of (060) reflection consistent with Mg/(Mg+Fe+Mn) = 1.00. Optically, about modal 1% "heavy" minerals (huge index and birefringence). Rutile has its strongest reflection at 3.24 Angstroms but was not found optically (compare with GDS-158, "rutilated clinochlore").

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION
KEYWORD Oxide
ASCII Amount Weight
Percent, % Oxide
html

COMPOSITION: SiO2 31.3 wt% SiO₂

COMPOSITION: TiO2 0.20 wt% TiO₂

COMPOSITION: Al2O3 19.4 wt% Al₂O₃

COMPOSITION: Cr2O3 0.004 wt% Cr₂O₃

COMPOSITION: Fe2O3 1.16 wt% Fe₂O₃

COMPOSITION: MnO 0.02 wt% MnO

COMPOSITION: MgO 34.7 wt% MgO

COMPOSITION: CaO 0.04 wt% CaO

COMPOSITION: Na2O 0.20 wt% Na₂O

COMPOSITION: K2O 0.01 wt% K₂O

COMPOSITION: P2O5 0.01 wt% P₂O₅

COMPOSITION: LOI 13.3 wt% LOI

COMPOSITION: Total 100.344 wt%

COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S

COMPOSITION: New Total wt%

COMPOSITION_TRACE:

COMPOSITION KEYWORD	Oxide ASCII	Amount	Weight Percent, %	Oxide html
COMPOSITION:	SiO2	31.3	wt%	SiO₂
COMPOSITION:	TiO2	0.20	wt%	TiO₂
COMPOSITION:	Al2O3	19.4	wt%	Al₂O₃
COMPOSITION:	Cr2O3	0.004	wt%	Cr₂O₃
COMPOSITION:	Fe2O3	1.16	wt%	Fe₂O₃
COMPOSITION:	MnO	0.02	wt%	MnO
COMPOSITION:	MgO	34.7	wt%	MgO
COMPOSITION:	CaO	0.04	wt%	CaO
COMPOSITION:	Na2O	0.20	wt%	Na₂O
COMPOSITION:	K2O	0.01	wt%	K₂O
COMPOSITION:	P2O5	0.01	wt%	P₂O₅
COMPOSITION:	LOI	13.3	wt%	LOI
COMPOSITION:	Total	100.344	wt%
COMPOSITION:	O=Cl,F,S		wt%	#correction for Cl, F, S
COMPOSITION:	New Total		wt%

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns