Ore Genesis pp 118-130 | Cite as

Atoll Texture in Minerals of the Cobaltite-Gersdorffite Series from the Raipas Mine, Finnmark, Norway

  • F. M. Vokes
  • G. S. Strand
Conference paper
Part of the Special Publication of the Society for Geology Applied to Mineral Deposits book series (MINERAL DEPOS., volume 2)

Abstract

Particularly fine examples of “atoll-texture” are shown by Co-Ni-Fe-(Cu) sulpharsenides in specimens from the disused Raipas mine near Alta, Finnmark, northern Norway. Reinvestigations by optical, electron microprobe, and X-ray diffraction techniques have shown that the atolls, and the grains from which they appear to have developed by core replacement, are composed of two mineral phases. One, with a general composition (Co,Ni,Fe,Cu)3As2S4 can be shown to be a Co-rich member of the cobaltite-gersdorffite series; the other phase, (Co,Ni,Fe,Cu)2AsS2, does not appear to correspond to any reported natural mineral having this general composition.

The nature of the often spheroidal grains from which the atolls have developed is not too certain. They bear certain resemblances to the general class of framboidal textures, though their compositions and internal structures are unusual.

Keywords

Cobalt Uranium Shale Dolomite Pyrite 

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References

  1. Bastin ES (1917) Significant mineralogical relations in silver ores of Cobalt, Ontario. Econ Geol 12: 219–236CrossRefGoogle Scholar
  2. Bayliss P (1969) X-ray data, optical anisotropism, and thermal stability of cobaltite, gersdorffite and ullmannite. Mineral Mag 31:26–33CrossRefGoogle Scholar
  3. Edwards AB (1954) Textures of the ore minerals and their significance. Inst Min Metall, Melbourne, Australia, 242 ppGoogle Scholar
  4. Farrand M (1970) Framboidal sulphides precipitated synthetically. Miner Deposita 5:237–247CrossRefGoogle Scholar
  5. Furnival GM (1939) A silver-pitchblende deposit at Contact Lake, in the Great Bear Lake area. Econ Geol 34:739–776CrossRefGoogle Scholar
  6. Grondijs HF, Schouten C (1937) A study of Mt. Isa ores. Econ Geol 32:407–450CrossRefGoogle Scholar
  7. Klemm DD, Weiser T (1965) Hochtemperierte Glanzkobalt-Gersdorffit-Mischkristalle von Outokumpu/Finnland. Neues Jahrb Mineral Monatsh 1965:236–241Google Scholar
  8. Krause H (1965) Idaite, Cu5FeS6 from Konnerud, near Drammen. Contributions to the mineralogy of Norway, no 33. Nor Geol Tidsskr 45:417–422Google Scholar
  9. Love LG (1964) Early diagenetic pyrite in fine-grained sediments and the genesis of sulphide ores. In: Amstutz GC (ed) Developments in sedimentology, vol II, Sedimentology and ore genesis. Elsevier, Amsterdam, pp 11–17Google Scholar
  10. Love LG, Zimmermann DO (1961) Bedded pyrite and microorganisms from the Mt. Isa shale. Econ Geol 56:873–896CrossRefGoogle Scholar
  11. Neumann H (1944) Silver deposits at Kongsberg. Nor Geol Unders Publ 162:133Google Scholar
  12. Petruk W (1971) Mineralogical characteristics of the deposits and textures of the ore minerals. Can Mineral 11:108–139Google Scholar
  13. Petruk W, Harris DC, Stewart JM (1971) Characteristics of the arsenides, sulpharsenides and antimonides. Can Mineral 11:150–186Google Scholar
  14. Ramdohr P (1969) The ore minerals and their intergrowths. Pergamon Press, Oxford, 1124 ppGoogle Scholar
  15. Rickard DT (1970) The origin of framboids. Lithos 3:269–293CrossRefGoogle Scholar
  16. Rosner B (1970) Mikrosonden-Untersuchungen an natürlichen Gersdorfflten. Neues Jahrb Mineral Monatsh 1970:483–498Google Scholar
  17. Schouten C (1937) Metasomatische Probleme, Amsterdam (quoted in Edwards 1954)Google Scholar
  18. Solomon MJ (1965) Investigations into sulfide mineralization at Mount Isa, Queensland. Econ Geol 60:737–765CrossRefGoogle Scholar
  19. Vokes FM (1955) Observations at Raipas Mine, Alta, Finnmark. Nor Geol Unders Publ 191 (Årbok 1954):103–114Google Scholar
  20. Vokes FM (1957a) Some copper parageneses from the Raipas formation of northern Norway. Nor Geol Unders Publ 200 (Årbok 1956):74–111Google Scholar
  21. Vokes FM (1957b) On the presence of minerals of the linnaeite series in some copper ores from the Raipas formation of northern Norway. Nor Geol Unders Publ 200 (Årbok 1956):112–120Google Scholar
  22. Vokes FM (1967) Linnaeite from the Precambrian Raipas Group of Finnmark, Norway. An investigation with the electron microprobe. Miner Deposita 2:11–25CrossRefGoogle Scholar
  23. Yund RA (1962) The system Ni-As-S; phase relations and mineralogical significance. Am J Sci 260:761–782CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1982

Authors and Affiliations

  • F. M. Vokes
    • 1
  • G. S. Strand
    • 1
  1. 1.Geologisk InstituttUniversitetet i TrondheimTrondheimNorway

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