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(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Clinochlore_Fe GDS157 Chlorite DESCRIPT
DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: GDS157
MINERAL_TYPE: Phyllosilicate
MINERAL: Ferroan Clinochlore (Ripidolite) (Chlorite group)
FORMULA: (Fe+2,Mg)5Al(Si3Al)O10(OH)8
FORMULA_HTML: (Fe+2,Mg)5Al(Si3Al)O10(OH)8
COLLECTION_LOCALITY: Flagstaff Hill, California
ORIGINAL_DONOR: Jim Post
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
This sample is described in:
Post, J.L. and C.C. Plummer, 1972, The chlorite series of Flagstaff Hill area, California: A preliminary investigation. Clays and Clay Minerals, v.20, pp271-283.
Jim Post, 1993, written communication.
The sample GDS157.b is formerly sample GDS307 and was ground and sieved from sample GDS157. GDS157.b is a sieved sample with sieve interval 75 to 150 microns.
IMAGE_OF_SAMPLE:
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
40 kV - 30 mA, 6.5-9.5 keV, smear mount (ripidolt.out); 45 kV -
35 mA, 7.3- 9.5 keV, random mount (ripidlt2.out)
References: Bailey (1988), Huebner's reference patterns
Found: Chlorite, type IIb, one weak but distinct reflection at
9.7 Angstroms (mica?), and one very weak reflection at 7.7
Angstroms.
Sought but not found: quartz
Comments: Many sharp reflections indicate very good crystallinity. Ripidlt2
is one of the best chlorite patterns I have ever seen. The chemical analysis
places this chlorite in the composition range once called ripidolite. Note that
the unidentified reflection at 7.7 Angstroms is also present in clinochlore
GDS158."
J.S. Huebner, J. Pickrell, and J. Randow, 1993, written communication.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: # XRF
| COMPOSITION KEYWORD |
Oxide ASCII |
Amount | Weight Percent, % |
Oxide html |
|---|---|---|---|---|
| COMPOSITION: | SiO2 | 25.2 | wt% | SiO2 |
| COMPOSITION: | TiO2 | 0.90 | wt% | TiO2 |
| COMPOSITION: | Al2O3 | 19.6 | wt% | Al2O3 |
| COMPOSITION: | Cr2O3 | 0.057 | wt% | Cr2O3 |
| COMPOSITION: | Fe2O3 | 25.3 | wt% | Fe2O3 |
| COMPOSITION: | NiO | 0.051 | wt% | NiO |
| COMPOSITION: | MnO | 0.11 | wt% | MnO |
| COMPOSITION: | MgO | 16.6 | wt% | MgO |
| COMPOSITION: | CaO | 0.11 | wt% | CaO |
| COMPOSITION: | Na2O | 0.27 | wt% | Na2O |
| COMPOSITION: | K2O | 0.03 | wt% | K2O |
| COMPOSITION: | LOI | 10.0 | wt% | LOI |
| COMPOSITION: | Total | 98.228 | wt% | |
| COMPOSITION: | O=Cl,F,S | wt% | #correction for Cl, F, S | |
| COMPOSITION: | New Total | wt% |
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
None
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
Low order gray interference color, green pleochroic color, basal
cleavage, all consistent with chlorite. No other mica obvious, some
brown Fe staining present in some grains. G. Swayze.
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1a2a3a4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
| LIB_SPECTRA_HED: | where | Wave Range | Av_Rs_Pwr | Comment |
|---|---|---|---|---|
| LIB_SPECTRA: | splib04a r 1076 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib05a r 1661 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib05a r 1977 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib05a r 1990 | 1.3-5.3µm | 200 | g.s.= |
| LIB_SPECTRA: | splib06a r 5542 | g.s.= | ||
| LIB_SPECTRA: | splib06a r 5556 | g.s.= | ||
| LIB_SPECTRA: | splib06a r 5580 | g.s.= | ||
| LIB_SPECTRA: | splib06a r 5621 | g.s.= |