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: Meionite WS701 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: WS701

MINERAL_TYPE: Tectosilicate

MINERAL: Meionite (Scapolite group)

FORMULA: Na4Al3Si9O24(Cl,OH)/Ca4Al6Si6O24(CO3,SO4)

FORMULA_HTML: Na₄Al₃Si₉O₂₄(Cl,O H)/Ca₄Al₆Si₆O₂₄(CO₃, SO₄)

COLLECTION_LOCALITY: Greenville, Quebec Canada

ORIGINAL_DONOR: Ward Science Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Forms series with Marialite.

Metamorphic mineral with composition suggestive of feldspars.

IMAGE_OF_SAMPLE:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Scapolite + feldspar + quartz (Norma Vergo).

More recent XRD reports the presence of prehnite in this sample.

END_XRD_ANALYSIS.

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

COMPOSITION
KEYWORD Oxide
ASCII Amount Weight
Percent, % Oxide
html

COMPOSITION: SiO2 49.6000 wt% SiO₂

COMPOSITION: TiO2 0.0420 wt% TiO₂

COMPOSITION: Al2O3 25.4500 wt% Al₂O₃

COMPOSITION: FeO 0.0100 wt% FeO

COMPOSITION: MnO 0.0280 wt% MnO

COMPOSITION: MgO 0.0640 wt% MgO

COMPOSITION: CaO 15.4300 wt% CaO

COMPOSITION: Na2O 4.6460 wt% Na₂O

COMPOSITION: K2O 0.5220 wt% K₂O

COMPOSITION: Cl 0.3940 wt% Cl

COMPOSITION: F 0.0180 wt% F

COMPOSITION: SO3 2.3140 wt% SO₃

COMPOSITION: CO2 0.7000 wt% CO₂

COMPOSITION: Total 99.2180 wt%

COMPOSITION: O=Cl,F,S .0965 wt% #correction for Cl, F, S

COMPOSITION: New Total 99.1215 wt%

COMPOSITION KEYWORD	Oxide ASCII	Amount	Weight Percent, %	Oxide html
COMPOSITION:	SiO2	49.6000	wt%	SiO₂
COMPOSITION:	TiO2	0.0420	wt%	TiO₂
COMPOSITION:	Al2O3	25.4500	wt%	Al₂O₃
COMPOSITION:	FeO	0.0100	wt%	FeO
COMPOSITION:	MnO	0.0280	wt%	MnO
COMPOSITION:	MgO	0.0640	wt%	MgO
COMPOSITION:	CaO	15.4300	wt%	CaO
COMPOSITION:	Na2O	4.6460	wt%	Na₂O
COMPOSITION:	K2O	0.5220	wt%	K₂O
COMPOSITION:	Cl	0.3940	wt%	Cl
COMPOSITION:	F	0.0180	wt%	F
COMPOSITION:	SO3	2.3140	wt%	SO₃
COMPOSITION:	CO2	0.7000	wt%	CO₂
COMPOSITION:	Total	99.2180	wt%
COMPOSITION:	O=Cl,F,S	.0965	wt%	#correction for Cl, F, S
COMPOSITION:	New Total	99.1215	wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

Average of 5 spots.

Wet chemical analysis indicates a wt% of 0.57 for C02.
(These values may be suspect because acid dissolution did not remove all CO₃)

1. Mol % SiO₂ includes .0160 mol % SiF₄.
Mol % SiO₂ includes .1880 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 anions per formula unit = 25.04397.
Number of oxygen equivalents per formula unit = 24.98935.

5. Cation site assignments: Standard clay-mineral default with changes.
Must occupy tetrahedral sites: Si Al
To big cation sites: Ti Fe⁺² Mn Mg

X_Me = 63.3 Me
X_Me = Ca/(Ca+Na) = 64.7 % Me

Sample: Mizzonite

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Prehnite may contribute many of the NIR spectral features.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2c3c4_ # WS701 # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns