(For further information on spectroscopy, see:
TITLE: Serpentine HS318 DESCRIPT
ORIGINAL_DONOR: Hunt and Salisbury Collection
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
"P-11 Serpentine 318B--Colorado. Mg3(Si2O5)- (OH)4: The principal occurrences of serpentine are those in which they are derived by alteration of ultrabasic rocks. Serpentine specimens, like talc, deviate little from the ideal composition. However, also like talc, small amounts of aluminum and iron may replace silicon and magnesium. This particular sample is burdened with magnetite contamination, but still displays ferric ion bands at 0.65 and 0.45µ as well as clearly visible OH features at 1.4µ and 2.34µ. This latter feature is attributed to a combination of the OH stretch with the Mg-OH bend."
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.
40 kV - 30 mA, 6.5-9.5 keV
File: serpn318.out, -.mdi (edge/random mount)
References: S.W. Bailey (1988, Clays and Clay Minerals 36, 193-213); FJWicks and DS O'Hanley (1988, MSA Reviews in Mineralogy 19, 91-167; JCPDS #11-386; Huebner's reference patterns.
Found: lizardite, minor chlorite, many unidentified but weak reflections
Comment: Excellent match to the JCPDS pattern. Strong pattern with some peak broadening. A member of Bailey's group C serpentines; probable 6T polytype of Wicks and O'Hanley, but with some discrepant intensities. The pattern is more complex than that of a 1T serpentine polytype.
J.S. Huebner, J. Pickrell, T. Schaefer, written communication(USGS)
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
SPECTRAL_PURITY: 1c2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
|LIB_SPECTRA:||splib04a r 4424||0.2-3.0µm||200||g.s.=|
|LIB_SPECTRA:||splib05a r 6189||0.2-3.0µm||200||g.s.=|
|LIB_SPECTRA:||splib06a r 20395||g.s.=|