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:
IMAGE_OF_SAMPLE:
NO PHOTO
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 and others (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 and others, 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J.S. Huebner J.Pickrell, T. Schaefer, unpublished data, written communication, USGS, Reston, VA (1994)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, EPMA, ICP(Trace), WChem
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1b2b3b4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns