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J.S. Huebner J.Pickrell, T. Schaefer, unpublished data, written communication, USGS, Reston, VA (1994)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

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 ____ 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=