Mortar (''Malta'')
Many of the street pavements in Venice are made up of traditional Masegno stones joined together with mortar. The jointing processes known as Giunto Fugato and Giunto Fugato con Stilatura a Ferro both use mortar to fill in gaps (known in italian as fuga) and join the stones together after they have been properly laid down. In general mortar is made up of a mixture of mostly sand and water with small amounts of other additives.
Malta di Calce
This is mortar with a lime based powder additive.[2]
Malta bastardo
This is a mixture of a couple different types of mortar.[2]
Malta di Calce Idraulica
This is the most commonly used mortar when laying Pavement in Venice. This particular mortar is designed to set even when water is present, making it ideal for the constantly flooded streets of Venice.[2]
Cement
The use of cement in jointing stones is FORBIDDEN.[2] Cement causes a number of problems to the stones and overall pavement. First of all cement is more impermeable than the Stones causing water to pool on the stone which creates puddles in the street and leads to the deterioration of the stone. In addition when trying to remove the stones for any type of Street Maintenance cement tends to stick to the stones, making the whole process much harder and causing stones to be cracked, damaged and discarded[2].