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Clark and others 2007 USGS Data Series 231
Spectral Library splib06a Sample Description

(For further information on spectroscopy, see: http://speclab.cr.usgs.gov)

TITLE: Prehnite+Muscovite BM1931,12 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: BM1931,12

MINERAL_TYPE: Tectosilicate

MINERAL: Mizzonite (Scapolite group)

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

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

COLLECTION_LOCALITY: Grenville, Argenteuil County, Quebec, Canada

ORIGINAL_DONOR: British 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 feldspars. There is a complete solid solution series between marialite and meionite.

Sample description, NIR, MID-IR spectra and analysis published in:

Swayze,G.A., and R.N. Clark, 1990, Infrared Spectra and Crystal Chemistry of Scapolites: Implications for Martian Mineralogy. J. Geophys Res. v. 95, pp. 14481-14495.

IMAGE_OF_SAMPLE:
NO PHOTO

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

From the 1980s-early 1990s:
Scapolite + muscovite + other(m). (Norma Vergo)
Note that spectrum does not show effect of muscovite. "Other" may be plagioclase. This spectrum closely resembles that of cleaned sample run on a Nicolet FTIR spectrometer. Therefore the features presented here are due to those of the scapolite. G. Swayze.

Once we understood the 2.35-micron features were due to phrenite and not muscovite, the presence of muscovite bands is also understood. Newer XRD shows phrenite and miscovite.

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 44.84 wt% SiO2
COMPOSITION: TiO2 0.0 wt% TiO2
COMPOSITION: Al2O3 28.77 wt% Al2O3
COMPOSITION: FeO 0.01 wt% FeO
COMPOSITION: MnO 0.0 wt% MnO
COMPOSITION: MgO 0.0 wt% MgO
COMPOSITION: CaO 19.74 wt% CaO
COMPOSITION: Na2O 2.57 wt% Na2O
COMPOSITION: K2O 0.33 wt% K2O
COMPOSITION: Cl 0.02 wt% Cl
COMPOSITION: F 0.0 wt% F
COMPOSITION: SO3 0.9 wt% SO3
COMPOSITION: CO2 3.43 wt% CO2
COMPOSITION: Total 100.64 wt%
COMPOSITION: O=Cl,F,S 0.004 wt% #correction for Cl, F, S
COMPOSITION: New Total 100.636 wt%

COMPOSITION_TRACE: Exists but is not included.

COMPOSITION_DISCUSSION:

%Me = 80. End-Member: Mizzonite.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Sample probably contains prehnite which may contribute some strong spectral features. This phase may be hard to differentiate from scapolite with x-ray diffraction analysis.Sample: Command not found. spectral features. This phase may be hard to differentiate from scapolite with x-ray diffraction analysis.spectral: Command not found. scapolite with x-ray diffraction analysis.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1c2c3c4_ # 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 3064 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4435 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 14023 g.s.=
LIB_SPECTRA: splib06a r 14037 g.s.=