DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: NMHN122689
MINERAL_TYPE: Inosilicate
MINERAL: Riebeckite (Amphibole group)
FORMULA: Na2Fe(+2)3Fe(+3)2Si8O22(OH)2
FORMULA_HTML: Na2Fe3+2Fe2+3Si8O22(OH)2
COLLECTION_LOCALITY: Hurricane Mountain, Conway, New Hampshire
ORIGINAL_DONOR: National Museum of Natural History
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
Individual grains of riebeckite appear very pure under the microscope (<1% impurities).
Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
Pure reibeckite.
Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
| COMPOSITION: | SiO2 | 50.32 | wt% | SiO2 |
| COMPOSITION: | TiO2 | 0.53 | wt% | TiO2 |
| COMPOSITION: | Al2O3 | 0.86 | wt% | Al2O3 |
| COMPOSITION: | FeO | 35.27 | wt% | FeO |
| COMPOSITION: | MnO | 1.12 | wt% | MnO |
| COMPOSITION: | MgO | 0.07 | wt% | MgO |
| COMPOSITION: | CaO | 0.08 | wt% | CaO |
| COMPOSITION: | Na2O | 7.95 | wt% | Na2O |
| COMPOSITION: | K2O | 1.41 | wt% | K2O |
| COMPOSITION: | Total | 97.61 | wt% |
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
Microprobe analysis of hand-picked smaple shows it to be homogeneous within and between grains, with typical riebeckite composition. Average of 10 samples.
Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.
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 4241 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.=