In the framework of ongoing research on the building stones and mortars used throughout the Middle Ages in the cities of Pisa and Lucca (western Tuscany), the chemical, mineralogical, petrographical and main physical properties of 72 green and white-pink quartzite samples from Mt. Pisano (Tuscany, Italy) were determined. Data was collected on unweathered materials sampled from currently operating or inactive quarries. All the analysed samples can be described as belonging to a single compositional “family”, whose members are mixtures, in different proportions, of silica and a “residue” with a nearly constant ratio amongst its chemical constituents.The white-pink quartzites have a quartz average content (71.60 %) somewhat higher than the green ones (64.93%). The green and white-pink quartzites have very similar overall properties, and both are extremely resistantto degradation.They differmostly in the averagevalues of the bulk density(2.61 g/cm3 and 2.44 g/cm3 for green and white-pink quartzites, respectively), water imbibition coefficient (0.793 % and 1.617 % by weight), porosity(3.39%and 9.40%by volume)and grain size (175 μm and 344 μm). The white-pinkquartziteswere used much more often in construction than the green ones, probably owing to easier quarrying. The different applicationsand degreesof degradationof these quartzitesare describedwith referenceto historicalmonuments in Pisa and Lucca.
|Autori:||Franzini M.; Lezzerini M.; Mannella L.|
|Titolo:||The stones of medieval buildings in Pisa and Lucca (western Tuscany, Italy). 3 – Green and white-pink quartzites from Mt. Pisano|
|Anno del prodotto:||2001|
|Digital Object Identifier (DOI):||10.1127/0935-1221/01/0013-0187|
|Appare nelle tipologie:||1.1 Articolo in rivista|