U.S. Geological Survey home page


Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

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

TITLE: Halloysite CM13 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: CM13

MINERAL_TYPE: Phyllosilicate

MINERAL: Halloysite (Kaolinite-Serpentine group)

FORMULA: Al2Si2O5(OH)4

FORMULA_HTML: Al2Si2O5(OH)4

COLLECTION_LOCALITY: Dragon Iron Mine, Eureka, Utah

ORIGINAL_DONOR: Clay Mineral Standard, Ward Natural Science Inc.

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Polymorphous with Dickite, Kaolinite, and Nacrite.

A spectrum for this sample was published by:

Clark, R.N., King, T.V.V., Klejwa, M., Swayze, G.A., and Vergo, N., 1990, High spectral resolution reflectance spectroscopy of minerals: Journal of Geophysical Research, v.g 95, no. 8B, p 12,653-12,680.

Who noted that the sample was spectrally pure.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Halloysite + quartz
less than 2µ 7A halloysite + smectite + trace 10A halloysite.
Spectrally pure. (Norma Vergo)

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 46.3 wt% SiO2
COMPOSITION: TiO2 0.11 wt% TiO2
COMPOSITION: Al2O3 35.2 wt% Al2O3
COMPOSITION: Fe2O3 0.72 wt% Fe2O3
COMPOSITION: FeO 0.02 wt% FeO
COMPOSITION: MnO less than 0.02 wt% MnO
COMPOSITION: MgO 0.31 wt% MgO
COMPOSITION: CaO 0.31 wt% CaO
COMPOSITION: Na2O less than 0.15 wt% Na2O
COMPOSITION: K2O less than 0.02 wt% K2O
COMPOSITION: P2O5 0.26 wt% P2O5
COMPOSITION: H2O+ 14.4 wt% H2O+
COMPOSITION: H2O- 1.80 wt% H2O-
COMPOSITION: H2O 16.2 wt% H2O
COMPOSITION: LOI 15.8 wt% LOI
COMPOSITION: Total wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

COMPOSITION_TRACE:

None

COMPOSITION_DISCUSSION:

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

Induced Coupled Plasma trace analysis exists but is not yet included.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Bimodal Grain Size Distribution:
mode 1: 670 µm @ 95 vol%
mode 2: 35 µm @ 5 vol%

avg. grain size = 650 µm

Sample is not isotropic under cross-polarized light. About 1 vol% of sample has iron-oxide staining. Larger grains are 50% coated with smaller grains. Because sample is not isotropic I think sample has other clay contaminants probably up to 50 vol%. G. Swayze.

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

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 1942 0.2-3.0µm 200 g.s.= 650 µm
LIB_SPECTRA: splib05a r 3028 0.2-3.0µm 200 g.s.=


USA.gov logo  Take Pride in America button