In South Estonia, the mineral parageneses
of intermediate and mafic metavolcanics and Al-rich gneisses correspond to the granulite facies.
The mineralized clefts showing these parageneses
are distributed through a zone of the Gotthard and southern Aare massifs with an axis running roughly between the Fellital, in the east-northeast, through the Goschener Valley, the Furka Pass and Grimsel Pass areas, the Zinggenstock, and finally, in the west-southwest, to the Fieschergletscher (Fiesch Glacier, above the village of Fiesch).
During the last two years, numerous hubeite-bearing specimens have come on the mineral market, representing at least two distinct parageneses. It occurs as isolated clusters of crystals, up to a few millimeters across, perched on euhedral crystals of transparent to white quartz (Fig.
Of course, this does not preclude the occurrence of this mineral here, particularly in view of the variety of parageneses of hubeite.
Assemblages and parageneses
similar to those at La Combe de la Selle have been found at other deposits around Bourg d'Oisans.
Below, only minerals of the crystal-bearing parageneses
- i.e., true cleft minerals - are described; of the minerals of the country rock, only those which recrystallized within the cavities (e.g., garnets, zircon) are listed.
Kainosite-(Y) occurs at Puiva in two different parageneses
: kainosite (I) is found as a cleft filling with chlorite and fluorapophyllite, and on terminal faces of quartz crystals, where it may be intergrown with ancylite; in these cases, pyrite occurs as a still later growth on the two rare-earth species.
Deutzmann (1961), after studying hundreds of polished sections from the Tervuren Museum, concluded that there were two parageneses, one formed at a rather high temperature (corresponding to the first two phases of other authors, e.g.
(1974) Paragenese des sulfures de cuivre dans les gisements du Shaba, (Zaire): Part I.