Hydroxyl-Apatite

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Phosphate

Sample ID

WS425

Collection Locality

near Cokeville, Wyoming

Spectral Purity

1b2b3b4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

None # XRF, EPMA, ICP(Trace), WChem COMPOSITION_TRACE: None

Sample Description

IMAGE_OF_SAMPLE: NO PHOTO

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 J.S. Huebner J.Pickrell, T. Schaefer, unpublished data, written communication, USGS, Reston, VA (1994)

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801