DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: M3542

MINERAL_TYPE: Phyllosilicate

MINERAL: Cronstedtite (Kaolinite-Serpentine group)

FORMULA: Fe+22Fe+3(Si,Fe+3)O5(OH)4

FORMULA_HTML: Fe₂⁺²Fe⁺³(Si,Fe⁺³)O₅(OH)₄

COLLECTION_LOCALITY: Cornwall, England

ORIGINAL_DONOR: Ed Olsen, Field Museum of Natural History

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Agrees with cronstedtite pattern PDF 17-470 (Ed Olsen, personal communication).

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

The cronstedtite occurs with quartz and may contain as much as 5% quartz (E. Olsen, personal communication). Spectrally there is no evidence of the presence of quartz.

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 1301 0.2-3.0µm 200

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

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