Mosaic is the art of creating images with an assemblage of small pieces of colored glass, stone, or other materials. It may be a technique of decorative art, an aspect of interior decoration, or of cultural and spiritual significance as in a cathedral. Small pieces, normally roughly cubic, of stone or glass of different colors, known as tesserae, (diminutive tessellae), are used to create a pattern or picture.

The earliest known examples of mosaics made of different materials were found at a temple building in Ubaid, Mesopotamia, and are dated to the second half of 3rd millennium BC. They consist of pieces of colored stones, shells and ivory. Excavations at Susa and Choqa Zanbil show evidence of the first glazed tiles, dating from around 1500 BC. However, mosaic patterns were not used until the times of Sassanid Empire and Roman influence.

Mosaics of the 4th century BC are found in the Macedonian palace-city of Aegae and they enriched the floors of Hellenistic villas, and Roman dwellings from Britain to Dura-Europos. Splendid mosaic floors are found in Roman villas across north Africa, in places such as Carthage, and can still be seen in the extensive collection in Bardo Museum in Tunis, Tunisia. In Rome, Nero and his architects used mosaics to cover the surfaces of walls and ceilings in the Domus Aurea, built AD 64.

The mosaics of the Villa Romana del Casale near Piazza Armerina in Sicily are the largest collection of late Roman mosaics in situ in the world, and are protected as a UNESCO World Heritage Site. The large villa rustica, which was probably owned by Emperor Maximian, was built largely in the early 4th century. The mosaics were covered and protected for 700 years by a landslide that occurred in the 12th century. The most important pieces are the Circus Scene, the 64 m long Great Hunting Scene, the Little Hunt, the Labours of Hercules and the famous Bikini Girls, showing women exercising in modern-looking bikinis. The peristyle, the imperial apartments and the thermae were also decorated with ornamental and mythological mosaics. Other important examples of Roman mosaic art in Sicily were unearthed on the Piazza Vittoria in Palermo where two houses were discovered. The most important scenes there depicted Orpheus, Alexander the Great’s Hunt and the Four Seasons.

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