Glass Mosaic--Laminated Mix Brown

 

Mosaic of Eastern Roman emperor Justinian I, 6th century

Roman mosaics are constructed from geometrical blocks called tesserae,^[11] placed together to create the shapes of figures, motifs and patterns.^[3] Materials for tesserae were obtained from local sources of natural stone, with the additions of cut brick, tile and pottery creating coloured shades of, predominantly, blue, black, red, white and yellow.^[3] Polychrome patterns were most common, but monochrome examples are known.^[12] Marble and glass were occasionally used as tesserae,^[13] as were small pebbles,^[14] and precious metals like gold.^[15]

Mosaic decoration was not just confined to floors but featured on walls and vaults as well. Traces of guidelines have been found beneath some mosaics, either scored into or painted onto the mortar bedding. The design might also be pegged out in string,^[3] or mounted in a wooden frame.^[16]

The collapse of buildings in antiquity can, paradoxically, both irrevocably destroy mosaics or protect and preserve them.^[3]