DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS336

MINERAL_TYPE: Inosilicate

MINERAL: Richterite (Amphibole group)

FORMULA: Na2Ca(Mg,Fe2+,Mn,Fe3+,Al)5(Si8O22)(OH,F)2

FORMULA_HTML: Na₂Ca(Mg,Fe²⁺,Mn,Fe³⁺,Al)₅(Si₈O₂₂)(OH,F)₂

COLLECTION_LOCALITY: Sweden

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

"I-21 Richterite 336B--Sweden. Na₂Ca(Mg, Fe²⁺, Mn, Fe³⁺, Al)₅(Si₈O₂₂)(OH, F)₂: This mineral occurs in thermally metamorphosed limestones and skarns, and is also found as a hydrothermal product in veins in alkaline igneous rocks. This sample is contaminated with 30% magnetite, which reduces the overall reflectivity. It would also serve to quench the iron bands, were any displayed. However, the curve shown is for a sample cleaned of all magnetite, and it is still surprisingly free of electronic transition bands for an amphibole. The only well defined features are the 1.4µ OH band, which is clearly doubled, and the two OH bands near 2.32µ and 2.38µ."

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.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE:

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 4219 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.=