MINERAL: Clintonite (Mica group)
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
40 kV - 30 mA (clntnit.out); 45 kV - 35 mA, sample ground with
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.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem
SPECTRAL_PURITY: 1c2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns