Building Materials - Table of Contents.......................... Illustrated
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A pattern, either geometric or figurative, formed by inlaying small pieces of stone, tile, glass, or enamel into a cement, mortar, or plaster matrix.
It can be applied for the incrustation of the interior or the facade of the building. It can be used as the functional flooring or ceiling cover.
Tessera (plural: tesserae;pronounced TESS sa ra; TESS saree): an individual tile in a mosaic, usually formed in the shape of a cube. From the Greek for "four sided," the term is said to have first ben used by Pliny when referring to pavements made of such cubes. The pieces which make up a mosaic, usually a hard inorganic material such as
- opaque enamel,
- or other mineral substance, natural or man-made.
Opaque enamel: The substance made at the Vatican Mosaic Studio for use in the mosaics of St. Peter’s Basilica, and later for other pictorial and decorative objects. It was used as early as 1600, and gradually improved and increased in variety to over 28,000 different shades. It was made into cakes which were hammered or broken into cube-like pieces called tesserae.
Glass: colored glass or or clear glass backed with metal foils
Byzantine tesserae with gold leaf, in which case the glass pieces were flatter, with two glass pieces sandwiching the gold
In mosaic work, a small piece of stone, glass, ceramic, or other hard material cut in a cubical or some other regular shape.
The earliest tesserae, which by 200 BC had replaced natural pebbles in Hellenistic mosaics, were cut from marble and limestone. Stone tesserae remained dominant in mosaics into Roman times, but between the 3rd and 1st centuries BC tesserae of smalto, or colored glass, also began to be produced, cut from large slabs of glass that ranged from lightly tinted to opaque. These relatively fragile glass tesserae were used sparingly in floor mosaics to provide pure blues, reds, and greens that could not be found in the more durable natural stone;
with the advent of wall mosaic between the 1st and 3rd centuries AD, however, glass tesserae of every hue were produced to constitute the major part of this decoration, stone being mainly reserved for floors. Glass was the major material for wall and vault mosaics of Early Christian and Byzantine churches, and marble and limestone tesserae were frequently used in the depiction of faces, woolen garments, rocks, and other objects that required a soft or rough appearance.
Roman mosaic: Can refer to ancient Roman mosaics, but here refers to the opaque enamel mosaics made in Rome as distinguished from glass mosaics like those at St. Mark’s (Venice), or hardstone mosaics made in Florence.
The mosaic was used in ancient times - beautiful mosaic decorations can be found throughout the countries of the Roman Empire, in domestic and public spaces. The art of mosaic flourished in Early Christian and in Byzantine art - churches in Daphni (Greece) and in Ravenna (Italy) are the best examples. During eleventh and twelfth centuries mosaic decoration ornate the churches of Venice, Greece, Sicily and Rome. After a period of decline mosaic was rediscovered by the the Art Nouveau artists in the nineteenth century.
The richest, largest and most complex collection of Roman mosaics in the world is in the Villa del Casale in Sicily. It is a UNESCO World Heritage Site. The largest and most spectacular mosaic in Buffalo is in the Ellicott Square Building.
Mosaics and Early Christian Buildings
Mosaics played an important a role in the interiors of Early Christian buildings. When, under Constantine, Christianity suddenly became a public and official religion in Rome, not only were new buildings required to house the faithful, but wholesale programs of decoration for the churches also became necessary.
To advertise the new faith in all its diverse aspects - its dogma, scriptural narrative, and symbolism - and to instruct and edify the believer, acres of walls in dozens of new churches had to be filled in the style and medium that would carry the message most effectively.
Brilliant ornamental mosaics, with sparkling tesserae (small squares) of reflective glass, rather than the opaque, marble tesserae preferred by the Romans, almost immediately became the standard vehicle of expression.
Whereas Roman mosaics were mostly used as floors, the Byzantines specialized in covering walls and ceilings. The smalti were ungrouted, allowing light to reflect and refract within the glass. Also, they were set at slight angles to the wall, so that they caught the light in different ways. The gold tesserae sparkle as the viewer moves around within the building.
Examples from Buffalo:
- Illustration above: Ellicott Square Building Floor
- Guaranty Building Walls and ceiling
- St. Paul's Episcopal Cathedral Reredos and floor
- Delaware Avenue Baptist Church
- Bemis House Floor
- Market Arcade Building Floor
- Trinity Episcopal Church Floor