DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS107

MINERAL_TYPE: Tectosilicate

MINERAL: Microcline (Feldspar group)

FORMULA: KAlSi3O8

FORMULA_HTML: KAlSi₃O₈

COLLECTION_LOCALITY: Keystone, South Dakota

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Dimorphous with Orthoclase.

"The spectrum (107B) displays a very intense OH band near 1.4µ with an accompanying feature near 2.2µ. The very weak band near 1.9µ indicates only a very small amount of H₂O. The bands are consistent with the incipient alteration of this sample to kaolinite."

Sieve interval 74 - 250µm.

Hunt, G.R., J.W. Salisbury, and C.J. Lenhoff, 1973, Visible and near-infrared spectra of minerals and rocks: VI. Additional silicates. Modern Geology, v. 4, p. 85-106.

Note, however, that the 2.2-2.4 µm bands are those of muscovite (or similar mica), not kaolinite as noted by Hunt et al. That is confirmed by XRD below. - R. Clark

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Max. microcline + albite(L) + muscovite(m)

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Not done yet

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 3001 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.=