TITLE: Halloysite+Kaolinite CM29 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: CM29

MINERAL_TYPE: Phyllosilicate

MINERAL: Halloysite + Kaolinite (Kaolinite-Serpentine group)

FORMULA: Al2Si2O5(OH)4

FORMULA_HTML: Al2Si2O5(OH)4

COLLECTION_LOCALITY: Wagon Wheel Gap, Colorado

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.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Disordered kaolinite - a mixture of kaolinite and halloysite (from NIR data)] (Norma Vergo)

END_XRD_ANALYSIS.

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


COMPOSITION: SiO2 43.8 wt% SiO2
COMPOSITION: TiO2 <0.02 wt% TiO2
COMPOSITION: Al2O3 37.8 wt% Al2O3
COMPOSITION: Fe2O3 0.71 wt% Fe2O3
COMPOSITION: FeO 0.03 wt% FeO
COMPOSITION: MnO <0.02 wt% MnO
COMPOSITION: MgO 0.11 wt% MgO
COMPOSITION: CaO 0.22 wt% CaO
COMPOSITION: Na2O <0.15 wt% Na2O
COMPOSITION: K2O <0.06 wt% K2O
COMPOSITION: P2O5 0.21 wt% P2O5
COMPOSITION: H2O+ 14.8 wt% H2O+
COMPOSITION: H2O- 0.80 wt% H2O-
COMPOSITION: H2O 15.6 wt% H2O
COMPOSITION: LOI 15.4 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:

avg grain sz = 300 µm

Sample is isotropic in cross-polarized light. Clumps of plates? visible under microscope. Plates suggest kaolinite, but SEM work I have done on this sample shows at least some grains are hollow tubes which indicates sample is partially halloysite. This sample is then probably a mix of kaolinite and halloysite. G. Swayze.

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 1963 0.2-3.0µm 200 g.s.= 300 µm

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

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