Sand and silt deposits inside the Ponteranica Conglomerate of Permian age.
These deposits crop out above Lake Trona at an elevation of about 2300 m, 400 m west of Bocca di Trona Pass, and contain remains of a new fossil conifer, named Cassinisia orobica (Kerp et al., 1996). Imprints of the apical parts of cone scales are sometimes filled with colourless or violet fluorite and calcite.

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Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ Calcite

ⓘ Fluorite

2 valid minerals.

Detailed Mineral List:

ⓘ Calcite

Formula: CaCO₃

References:

Bedognè, F., Montrasio, A., Sciesa, E. (2006) I minerali della media-alta Valtellina, delle Orobie valtellinesi e della Val Poschiavo. Aggiornamenti sulle altre località della provincia di Sondrio. Bettini, Sondrio, 255 pp.

ⓘ Fluorite

Formula: CaF₂

References:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 3 - Halides
ⓘ	Fluorite	3.AB.25	CaF₂
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃

List of minerals for each chemical element

C	Carbon
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Calcite	CaCO₃
F	Fluorine
F	ⓘ Fluorite	CaF₂
Ca	Calcium
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Fluorite	CaF₂

Other Regions, Features and Areas containing this locality

Eurasian PlateTectonic Plate

DinaridesAccretionary Complex

EuropeContinent

The AlpsMountain Range

Italy

Lombardy
- Sondrio Province
  - Bitto di Gerola Valley (Gerola Valley)Valley
  - ValtellinaValley

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References

Kerp, H., Penati, F., Brambilla, G., Clement-Westerhof, J.A., van Bergen, P. (1996): Aspects of Permian paleobotany and palynology. XVI. Three-dimensionally preserved stromatolite-incrusted conifers from the Permian of the western Orobic Alps (northern Italy). rev. of Paleobot. and Palynol., 91, 63-84.

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Bocca di Trona Pass, Gerola Alta, Sondrio Province, Lombardy, ItalyiRegional Level TypesBocca di Trona PassPass Gerola AltaMunicipality Sondrio ProvinceProvince LombardyRegion ItalyCountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }