ROCKS CAN BE CLASSIFIED ACCORDING TO DIFFERENT PARAMETERS.
ACCORDING TO THEIR COMMERCIAL AND PETROGRAPHIC CLASSIFICATION, THEY CAN BE DIVIDED INTO MARBLE, GRANITE, TRAVERTINE AND STONE.
THE USE OF STONE MATERIALS IN ARCHITECTURE, IN THE PRODUCTION OF UTILITARIAN OBJECTS AND SCULPTURAL WORKS IS VERY ANCIENT AND COVERS A VAST GEOGRAPHICAL AREA, FROM THE CELTIC AND DRUID CIVILISATIONS, MESOPOTAMIAN AND EGYPTIAN, GREEK AND ROMAN, TO THE GREAT WORKS OF THE MIDDLE AGES, THE RENAISSANCE AND THE BAROQUE, RIGHT UP TO THE PRESENT DAY.
MARBLE IS A CRYSTALLINE, COMPACT, POLISHABLE ROCK COMPOSED MAINLY OF MINERALS WITH A MOHS HARDNESS OF 3 TO 4 (SUCH AS CALCITE, DOLOMITE, SERPENTINE).
THE LOW REFRACTIVE INDEX OF CALCITE ALLOWS LIGHT TO 'PENETRATE' THE SURFACE OF THE STONE BEFORE BEING REFLECTED. THIS RESULTS IN A PARTICULARLY BRIGHT, CLEAR AND TRANSLUCENT APPEARANCE, REMINISCENT OF THE WAXY APPEARANCE OF HUMAN SKIN, AND HAS MADE MARBLE PARTICULARLY POPULAR WITH SCULPTORS.
THE TERM 'MARBLE' DERIVES FROM THE GREEK WORD 'MARMAROS', ALLUDING TO THE SPLENDOUR OF THE STONE AFTER IT HAS BEEN POLISHED.
IT IS AN IDEAL MATERIAL FOR ITS DURABILITY, STRUCTURAL STRENGTH AND AESTHETIC QUALITIES, WHICH ARE EXPRESSED BOTH IN THE COLOURED MARBLES, MAINLY FROM EGYPT, TUNISIA, PERSIA, ANATOLIA AND THE PYRENEES, AND IN THE WHITE MARBLES, CONSIDERED THE MOST REFINED AND PRIZED IN SCULPTURE, SUCH AS THOSE QUARRIED IN THE LUNI QUARRIES OF CARRARA SINCE THE TIME OF THE ROMAN EMPIRE.
INSILVIS PREFERS ITALIAN MARBLES QUARRIED LOCALLY.
BIANCONE D'ASIAGO OR BIANCO PERLINO MARBLE IS QUARRIED ON THE ASIAGO PLATEAU IN THE PROVINCE OF VICENZA, A CITY IN THE VENETO REGION OF ITALY.
IT IS A SEDIMENTARY ROCK WITH REGULAR LAYERING, FORMED FROM COMPACT CALCAREOUS MUD, WITH THE PRESENCE OF MICROFOSSILS, SOMETIMES AMMONITES, NODULES AND LENSES OF DARK GREY-BLACK, OLIVE-BROWN OR DARK BROWN FLINT.
IT IS WHITISH IN COLOUR, WITH A COMPACT TEXTURE AND FINE OR VERY FINE GRAINS.
IT CAN BE HONED, BRUSHED AND POLISHED.
PIETRA PIASENTINA IS STILL QUARRIED IN THE FOOTHILLS OF THE JULIAN PRE-ALPS, IN THE PROVINCE OF UDINE, IN THE NORTH-EAST OF THE ITALIAN REGION OF FRIULI VENEZIA GIULIA.
IT WAS USED BY THE ROMANS TO BUILD THE FORUM JULII, NOW CIVIDALE DEL FRIULI, FOUNDED BY JULIUS CAESAR IN THE 1ST CENTURY BC, AND BY ARCHITECTS SUCH AS ANDREA PALLADIO.
IN THE FIELD OF ARCHITECTURE, PIETRA PIASENTINA IS HIGHLY APPRECIATED FOR ITS EXTRAORDINARY COLOUR NUANCES AND ITS EASE OF USE, BOTH INDOORS AND OUTDOORS.
PIETRA PIASENTINA IS A SEDIMENTARY LIMESTONE OF SECONDARY ORIGIN, CREATED BY GRAVITATIONAL PROCESSES TRIGGERED BY TECTONIC MOVEMENTS IN THE EARTH'S CRUST.
PIASENTINA STONE IS VERY COMPACT AND HAS EXCELLENT COMPRESSIVE AND FLEXURAL STRENGTH; IT DOES NOT CHANGE COLOUR WHEN EXPOSED TO WEATHERING AND CAN WITHSTAND MANY CYCLES OF FROST AND WEAR.
ITS COLOUR IS BASIC GREY, BUT IT OFFERS A WIDE RANGE OF SHADES, FROM THE LIGHT GREY OF THE SAWING PROCESS TO THE DARK GREY OF THE POLISHING PROCESS, WITH SLIGHT WHITE VEINS AND COLOURED STREAKS TENDING TOWARDS BROWN.