In the past, building construction was mainly carried out using local materials, in particular those that could be worked into square blocks and also with aesthetic characteristics for decorative use.
PIPERNO
Piperno is a rock resulting from the largest explosive eruption occurred in the Phlegraean Fields about 40,000 years ago, formed by the deposition of pyroclastic flows at high temperature and the subsequent welding of particles (ash and pumice). Underground quarries, now inactive, were present along the slopes of Quarto, Pianura and Soccavo in Naples. Piperno played a primary role in the historical building of the region because it was used at different times for the construction of important architectural works.
TUFF
In the Neapolitan and Vesuvian area, yellow tuff has had a massive use, resulting from explosive eruptions of the Phlegraean Fields. Among the various yellow tuffs two varieties are those widely used: the yellow Neapolitan tuff (from an eruption occurred 15,000 years ago, extracted in the Neapolitan area) and the Campania tuff (from the same eruption that produced the piperno, occurred 40,000 years ago and largely extracted in the Piana Campana and Apennine valleys). Both tuffs owe their yellow colour to a process of transformation of the ash glass into zeolites, which led to their lithification.