Pietra gray is an Italian term for the unique Persian marble with a gray background.There are about 250 Petra gray quarries in Iran, which annually produce and sell large quantities of this unique stone all around the world. In addition to the exceptional beauty of this marble, its low water absorption as well as its high resistance, have made it a classy material to be used in both interior and exterior design. This marble has 5 different sorts in terms of design and color as follows:1- Dark background with few white veins2- Dark background with medium to high white veins3. Light background with few white veins4- Light background with medium to the high white veins5. Light background with bright sparklesIts polished type is used extensively in commercial areas such as hotel lobbies, banks and shopping malls. In Europe, its honed type is famous especially for the kitchen interior design.Moreover, the honed type has a very high resistance and a stylish classic look which gives a sense of prestige to any home in inhabits.