Case Bardot, Fomarco, Marmazza Valley (Toppa Valley), Pieve Vergonte, Verbano-Cusio-Ossola Province, Piedmont, Italyi

Regional Level Types
Case Bardot	Outcrop
Fomarco	Village
Marmazza Valley (Toppa Valley)	Valley
Pieve Vergonte	Commune
Verbano-Cusio-Ossola Province	Province
Piedmont	Region
Italy	- not defined -

Case Bardot, Fomarco, Marmazza Valley (Toppa Valley), Ossola Valley, Verbano-Cusio-Ossola Province, Piedmont, Italy

Quartz veins bearing argentiferous galena and scheelite, crosscuting the main schistosity of the Fobello-Rimella schists, in the vicinity of Case Bardot.

In the 1880s a short adit was excavated in a quartz vein just below Case Bardot, on the left side of the dry rivulet named Rivo Toietti. Another adit (coordinates: 46.011203013 N, 8.259645402 E), presently used as a water reservoir, was excavated at a lower elevation near Case Toietti.

Stolzite as well as the secondary minerals have been found a few meters above the entrance of the upper adit in a quartz vein outcrop, in association with galena veinlets and partly altered scheelite nodules (Conforti et al. 1992; Gentile & Vignola, 1992; Albertini et al., 2005). Stolzite, the most interesting mineral of this locality, appears as bipyramidal, tabular or pseudocubic crystals, up to 2-3 mm in size, orange to orange-yellow to yellow-greenish in colour, usually associated with galena and scheelite; iso-oriented aggregates of tabular stolzite crystals in scheelite have been rarely observed.

In the period 2008-2009, during the construction of the connecting road named "Case Sparse" - Lot 1, a road cut near Case Bardot evidenced some analogous quartz veins, which yielded abundant stolzite microcrystals.


Also scheelite samples from this locality, studied by Uspensky et al. (1998), showed a trace element content and the typical REE³⁺ distribution observed in the scheelites of other localities of the Marmazza Valley (Toppa Valley) ore field.




Note: this locality was errouneosly indicated by Conforti et al. (1992) as "Filone della Piana" [Piana vein]. This erroneous toponym is also used by Uspensky et al. (1998) to indicate the origin of two of the three analyzed scheelite samples from Fomarco. The error is due to the existence of two quite similar toponyms in the area: Piano and Piana (Alla Piana). The stolzite-scheelite locality is located inside the boundaries of the area Case Toietti - Piano - Case Bardot - Case Prossi, in which a prospecting permit for argentiferous galena was granted to Giuseppe Cicoletti and Vincenzo Bassi in 1881; on the contrary, at Piana (Alla Piana) locality, situated a little further north, a prospecting permit for auriferous pyrite was granted to Anna Maria Trabucchi in 1880.

Other Regions, Features and Areas containing this locality

References