NGT41-2/3/4-08
1961
Contributions to the mineralogy of Norway. No. 9. On the occurrence of two rare phosphates in the Ødegården Apatite Mines, Bamble, South Norway 1. A variety of Woodhouseite. 2. Whitelockite.
41
2, 3, 4
233-246

A description is given of varieties of woodhouseite and whitlockite found in specimens from the apatite-rich veins cutting the Precambrian rocks at Ødegårdens verk, Bamble, S. Norway. The minerals occur, together with quartz, in pockets within a matrix of chlor-hydroxy-oxyapatite. Physical and optical data are given for both minerals, together with x-ray powder diffraction data. A semi-quantitative spectrographic analysis of the whitlockite is included.

The woodhouseite is a purple variety with lattice dimensions of ah 7,001, ch 16,265, c/a 2,325, ar 6,76 and < a 62° 22'; its optical constants are Ne = 1,669 ( ±0,003), NO = 1, 662 ( ± 0,003), Ne -NO 0,007 ( ± 0,003), uniaxial positive (or occasionally biaxial with 2V of 10° to 20°). An unidentified alteration product after woodhouseite is also described.

The whitlockite is a green variety, containing approximately 0,3% V2O5, with optical constants: NO = 1,620 ( ± 0.003), Ne = 1,623 ( ± 0,003), Ne - NO 0,003 ( ± 0,003), uniaxial negative. It is concluded that the minerals in these pockets represent either final residual products of crystallisation within the apatite vein or that they were formed during a later period of metamorphism, metasomatism and hydrothermal activity which may have affected the apatite veins.

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