Chlorapatite

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Phosphate

Sample ID

WS423

Collection Locality

Snarum, Norway

Spectral Purity

1c2b3b4_ # 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:

Sample Description

Single large brown crystal with indistict cleavage. IMAGE_OF_SAMPLE:

XRD Analysis

40 kV - 30 mA, 6.5-9.5 keV Reference: JCPDS #33-271 (synthetic chlorapatite); Hughes and others (1989) Found: Apatite plus un indexed weak reflections at 26.61 [near position of the strongest quartz reflection, the (101)] and at 25.94, 31.71, 32.84, and 43.4 degrees 2 theta. Cell dimensions: a=9.6078(8), c=6.7912(8) Angstroms, using BaF2 internal standard Comment: an apatite, probably Cl-rich, plus at least one, and probably two, minor additional phases. Extraordinarily clear pattern with many sharp peaks indicating high degree of crystallinity and compositional homogeneity. Synthetic chlorapatite is reported to have a=9.641 and c=6.771 Angstroms; natural chlorapatite with F.09Cl.88 has a=9.598, c=6.776 Angstroms. Although the cell dimensions of WS416 appear similar to those of the analyzed natural fluorapatite, the cell dimensions of the reference synthetic and natural fluorapatites do not agree. Thus, there is uncertainty in the composition of WS416. J.S. Huebner, J. Pickrell, T. Schaefer, unpublished data, written communication, U.S.G.S., Reston, VA (1994) additional XRD analysis (B. Benzel): Chloroapatite (96%) Hydroxyapatite (4%)

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801