Blaubleibender covellite and its relationship to normal covellite
- Cite this article as:
- Putnis, A., Grace, J. & Cameron, W.E. Contr. Mineral. and Petrol. (1977) 60: 209. doi:10.1007/BF00372282
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Both natural and synthetic samples of blaubleibender (blue-remaining) covellite have been studied by reflected light microscopy, electron probe microanalysis and electron microscopy and diffraction. The natural sample of composition Cu1.20S has a √19a × √19a superstructure based on the hexagonal coveilite subcell (side a). The synthetic sample of composition Cu1.10S has a 2√7 a × 2 √7a superstructure. In both cases the phases are homogeneous. The evidence suggests that the recognition of two distinct types of blaubleibender covellite may be an oversimplification, and that a series of metastable superstructures based on the covellite structure may exist.