ABSTRACT
The province of Bergamo has provided architecture with a large number of sedimentary rocks because the territory is characterized by geological formations which include three districts: the sedimentary series of the Southern Alps of the Mesozoic (a grey or brown limestone - Abbazia, a pink limestone with red and white veins and variegations - Arabescato orobico, a yellowish-brown calcarenite - Pietra di Credaro, other limestones like Rosso di Entratico and Nero di Bergamo, a grey sandstone - Sarnico, a grey evaporite - Volpinite, a pink dolostone - Zandobbio); the Neogene continental deposits (two important conglomerates - Ceppo del Brembo, Ceppo del lago di Iseo and other similar stones); the “Po Synthem” of Quaternary deposits (sands, gravels and pebbles).
The aforementioned stones have been used in architecture mainly as squared blocks, such as conglomerates (i.e. Ceppo del Brembo was the most employed stone in Milan and Lombard architecture), while the coloured stone ones have been used for carving and sculpture (i.e. Baroque altars).
