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(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Clintonite NMNH126553 DESCRIPT
DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: NMNH126553
MINERAL_TYPE: Phyllosilicate
MINERAL: Clintonite (Mica group)
FORMULA: Ca(Mg,Al)3(Al3Si)O10(OH)2
FORMULA_HTML: Ca(Mg,Al)3(Al3Si)O10(OH)2
COLLECTION_LOCALITY: Copper Mtn, Prince of Wales Island, Alaska
ORIGINAL_DONOR: National Museum of Natural History
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
IMAGE_OF_SAMPLE:
NO PHOTO
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
40 kV - 30 mA (clntnit.out); 45 kV - 35 mA, sample ground with
glass (clntnit2.out);
40 kV - 30 mA, random mount (clntnt3.out),
all with single channel analyzer set at 6.5-9.5 keV.
References: calculated xanthophyllite pattern of Borg and Smith
(1969); JCPDS #20-321; 1M and 2M1 patterns calculated
by H.T. Evans, Jr., using Akhundov and others (1961) and
Takeuchi (1965)
Found: Clintonite 1M, a subordinate unidentified phase, and minor
chlorite.
Comments: Persistent preferred orientation makes indexing, and thus
complete interpretation, of these patterns uncertain. I
refined the cell to a = 5.202(2), b = 9.808(6), c = 9.815(3),
and Beta = 100.17(3) degrees, but uncertainties in indexing increase
the uncertainty in the cell dimensions over the uncertainties
shown. The observed pattern matches the calculated 1M
pattern much more closely than the 2M1 pattern;
nevertheless, some intensity variations are bizarre.
Residual reflections consist of weak, broad chlorite (001)
and (002) reflections and 11 moderate to very weak, but
very sharp, reflections of an unidentified phase, perhaps
a layer silicate. (This unidentified phase may have
additional strong reflections that overlap with the
clintonite). The pattern is most unusual in that the
three phases can be distinguished by the sharpness of
their peaks; for this reason I doubt that there are two
unidentified phases.
J.S. Huebner, J. Pickrell, and T. Schaefer, 1994, written communication.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1c2_3_4_ # 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 1175 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib05a r 2103 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib06a r 6008 | g.s.= |