Name: Dolomite vein
Classification: Carbonite cement in sedimentary carbonate rockcarbanatica
Mineral composition: Dolomite, calcite
Fossils:none
Location: Mount Cernera (46°28'33.90"N 12° 3'29.02"E)
Formation: Mount Fernazza formation (chaotic heterogeneous)
Era: Upper Ladinic (approximately 238 million years ago)
Depositional environment: deep-water submarine landslides

dolomia

In the centre of this photograph you can clearly see crystals of dolomite, a mineral that contains magnesium, calcium, carbon and oxygen and that makes up the most typical Dolomite rocks.
Dolomite crystals are usually smaller, but these (from a vein of dolomite in a sample collected at the foot of Mount Cernera close to Forcella Giau) were formed in the subsurface at high temperatures. This can be deduced from the fact that the crystals have slightly curved faces. When dolomite

has curved faces, this particular form is called “saddle dolomite” (because the shape of the isolated crystals resembles that of a saddle), and it is only formed at temperatures in excess of 100-120 degrees Celsius. This dolomite was formed in a vein where very hot water circulated, close to the abandoned mine of Col Piombin. The hot liquids deposited iron, lead and zinc minerals which were still exploited at the beginning of the last century.

 

GALLERY