Tessera

For other uses, seeTessera (disambiguation).

"Abaciscus" redirects here. For the moth genus, seeAbaciscus(moth).

Tesserae of a mosaic of doves drinking at a golden basin, 1st century AD,National Archaeological Museum,Naples,Italy

Atessera(plural:tesserae,diminutivetessella) is an individualtile,usually formed in the shape of asquare,used in creating amosaic.It is also known as anabaciscusorabaculus.

The unique illuminating effect of golden tesserae,Cappella PalatinainPalermo,Sicily,12th century

A mosaic made from tesserae inSt Peter's Basilica,Vatican State,Italy

A close up of the bottom left corner of the picture above. Close inspection of the full picture reveals the individual tesserae.

Historical tesserae

Apse mosaic of the Virgin Mother and Child,Hagia Sophia,featuring intensely luminous golden tesserae

The oldest known tesserae date to the 3rd millennium BC, discovered in the ancient city ofShahdadinKermanprovince,Iran.

Inearly antiquity,mosaicswere formed from naturally formed coloredpebbles.By roughly 200 BC cut stone tesserae were being used inHellenistic-Greek mosaics.For instance, a large body of surviving material from the Hellenistic period can be found in themosaics of Delos,Greece, dating to the late 2nd century BC.Ancient Romandecorativemosaic panelsandfloor mosaicswere also produced during the 2nd century BC, particularly at sites such asPompeii.Marbleorlimestonewere cut into small cubes and arranged into representational designs and geometric patterns.

Later, tesserae were made from colored glass, or clear glass backed with metal foils. TheByzantinesused tesserae withgold leaf,in which case the glass pieces were flatter, with two glass piecessandwiching the gold.This produced a golden reflection emanating from in between the tesserae as well as their front, causing a far richer and more luminous effect than even plain gold leaf would create.

Contemporary tesserae

Wooden block with hammer and hardy for cutting mosaic tiles.

Vitreous glass

These are manufactured glass tiles made to a uniform shape and size. They are made by molten glass being poured into trays and fired. An imprint of grooves is made on their underside for help with adhesion to cement when fixing.

Iridised, marbled, & metallic tesserae

Iridised (with a reflective quality), marbled (featuring contrasting and complementary colors), metallic (semi-transparent with gold or bronze veins), and millefiori (round handmade Murano tesserae with intricate patterns) tesserae are also widely used.

Ceramic tesserae

These are the cheapest range of bought materials and can be glazed or unglazed. The glazed ceramic tiles have the color painted onto the top of the clay and then fired to a high temperature in a kiln. The unglazed or body glazed version has the color mixed into the wet clay so the color runs through them. They vary in size.

Smalti

This is the classic mosaic material. It is opaque glass fired in large slabs in a kiln and then hand cut into small cubes with a hammer and hardy chisel. Their irregular finish makes them a wonderful reflector of light and this material is best used working straight into cement. It is produced in Venice and sold by colour and weight.

Gold smalti

This tile is made withgoldand silverleafsandwiched between two layers of glass and fired twice in the kiln to embed in the metal.

Mirror

Mirrorfragments are available as offcuts from glass cutting shops.

Stained glass

Opaquestained glasscomes as large sheets that can be cut into smaller sections with a glasscutter.

Household ceramic tiles and china

Various household objects, includingpottery shards,can be used, especially intrencadísor pique assiette technique.

See also

• Tessellation–describes tessellation patterns
• Mosaic–describes techniques for assembling tesserae into a design

External links

• Media related toTesseraat Wikimedia Commons