In 1580, a workshop called the Opificio Delle Pietra Dura was set up in Florence under the direction of Cosmo Medici. The Opificio continued production well into the 19th century, and still exists today but concentrates mainly on restorations.
The Pietra Dura technique involves use of a variety of natural stones and marbles that include agates, chalcedony, carnelian, lapis lazuli, onyx, malachite, mother of pearl, and others. Thin slices of these stones, which are cut with a small saw or copper wire and, are then were fitted closely together like a jig saw puzzle- usually into a bed of black marble - to form a decorative pattern. Black Belgian marble was commonly used to form the matt background into a variety of natural stones or various coloured glasses were intricately inlayed. Favourite Florentine subjects for Pietra Dura mosaics were flowers, leaves, birds and fruit.