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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Hydroxyl-Apatite WS425 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: WS425

MINERAL_TYPE: Phosphate

MINERAL: Hydroxylapatite (Apatite group)

FORMULA: Ca5(P04)3(OH)

FORMULA_HTML: Ca5(PO4)3(OH)

COLLECTION_LOCALITY: near Cokeville, Wyoming

ORIGINAL_DONOR: Wards Scientific

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV

Reference: JCPDS #25-166 [natural hydroxylapatite having (OH)_38CL_33F_29]; Hughes et al. (1989)

Found: apatite; very minor quartz [peaks in the position (100) and (101) reflections] plus an additional reflection at 29.7 degrees 2 theta (carbonate?)

Cell dimension: a=9.348(2), c=6.883(2) Angstroms, using Si internal standard

Comments:An apatite of unknown composition plus at least two additional phases are present. (Optics would be definitive for possible carbonate.) Broad reflections suggest poor crystallinity and/or compositional heterogeneity. This is reflected in the relatively poor quality of the cell refinement. Hydroxyl apatite having almost endmember composition Ca4.98P2.99O12F.06(OH).91CL.03 has a=9.417 and c=6.875 (Hughes et al., 1989), which do not agree with those of WS425.

J.S. Huebner J.Pickrell, T. Schaefer, unpublished data, written communication, USGS, Reston, VA (1994)

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: 1?2_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 2240 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 3404 0.2-3.0µm 200 g.s.=


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