TITLE: Sepiolite SepNev-1 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: SepNev-1 (1-26-87)

MINERAL_TYPE: Phyllosilicate

MINERAL: Sepiolite (Meerschaum)

FORMULA: Mg4Si6O15(OH)2*H2O

FORMULA_HTML: Mg4Si6O15(OH)2•H2O

COLLECTION_LOCALITY: Two Crows, Nevada

ORIGINAL_DONOR: Source Clay Mineral Repository

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Sepiolite is a hydrous magnesium silicate, claylike and a secondary mineral associated with serpentine.

Sample is white in color.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Spectrally pure: no dolomite

dolomite affects the continuum only; confirmed by Na-acetate buffer purification. (Norma Vergo)

END_XRD_ANALYSIS.

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


COMPOSITION: SiO2 50.9 wt% SiO2
COMPOSITION: TiO2 <0.02 wt% TiO2
COMPOSITION: Al2O3 0.45 wt% Al2O3
COMPOSITION: Fe2O3 0.08 wt% Fe2O3
COMPOSITION: FeO <0.01 wt% FeO
COMPOSITION: MnO <0.02 wt% MnO
COMPOSITION: MgO 22.3 wt% MgO
COMPOSITION: CaO 2.45 wt% CaO
COMPOSITION: Na2O 1.12 wt% Na2O
COMPOSITION: K2O 0.17 wt% K2O
COMPOSITION: P2O5 <0.05 wt% P2O5
COMPOSITION: H2O+ 10.6 wt% H2O+
COMPOSITION: H2O- 8.05 wt% H2O-
COMPOSITION: H2O 18.6 wt% H2O
COMPOSITION: LOI 20.0 wt% LOI
COMPOSITION: Total 97.56 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total 97.56 wt%

COMPOSITION_TRACE:

Analysis by E. Brandt, J.H. Christie, J. Taggart, Ardith J. Bartel, K. Stewart

Exists but needs to be included.

Trace analysis exists.

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1_2_3_4_

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment

LIB_SPECTRA: splib04a r 4380 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib04a r 4391 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=