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Istrian stone, pietra d'Istria, the characteristic group of building stones in the architecture of Venice, Istria and Dalmatia, is a dense type of impermeable limestone that was quarried in Istria, nowadays Croatia; between Portorož and Pula.[1][2][3] Limestone is a biogenetic stone composed of calcium carbonate from the tests and shells of marine creatures laid down over eons. Istrian stone approaches the compressive strength and density of marble, which is metamorphosed limestone. It is often loosely referred to as "marble", which is not strictly correct.
![](https://upload.wikimedia.org/wikipedia/commons/thumb/8/84/Pietra_d%27Istria.png/220px-Pietra_d%27Istria.png)
Venice, isolated in its lagoon, had no building stone at hand. The freshly quarried stone is salt-white or light yellowish, which weathers to a pale gray; the whiteness of Istrian stone contrasts well with coloured stones and brick. When Francesco, son of the architect Jacopo Sansovino, wrote Venetia citta nobilissima et singolare (1580) he emphasized the distinctive quality that Istrian stone and the coppery-red Verona brocatello limestone (so-called Veronese marble) lent to the city.[4] It was brought, Sansovino said, from Rovigno and Brioni on the Istrian coast.
Notes
[edit]- ^ Raffaella Geometrante, Dario Almesberger, Antonio Rizzo: Characterisation of the State of compression of Pietra D'Istria elements by Non Destructive Ultrasonic Technique.
- ^ M. Simunic Bursic, D. Aljinovic, S. Cancelliere: Kirmenjak-Pietra d'Istria: a preliminary investigation of its use in Venetian architectural heritage. In: Geological Society, London, Special Publications; 2007; v. 271; p. 63-68 (abstract)
- ^ Venice, an online exhibit produced in ARTH 470z at the University of Mary Washington : Istrian stone
- ^ Paul Hills, Venetian Colour: marble, mosaic, painting and glass, 1250-1550, 1999:65
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction