Kroke stone

from Wikipedia, the free encyclopedia
Opus sectile with dark green elements from the Kroke stone
Circle from Verde Antico in Odéon antique, Lyon

Krokeischer Stein or lapis Lacedaimonius and also Porfido verde antico (other names are lapis Croceus , lapis Taygetas , lapis Spartanus or porfido serpentino verde ) is a volcanic rock that was broken at Krokeai in Laconia .

Applications

The Kroke stone , a mainly green-colored volcanic rock with a porphyry to ophitic structure, was mainly used in antiquity for the manufacture of tools and vessels. Pausanias describes the place of discovery three kilometers southeast of Krokeai in his work “... served as decoration for sanctuaries, but especially the stone embellished swimming pools and water basins.” In the Roman-Germanic Museum in Cologne there is a wall mosaic with a on top right Example (green) is located. This leads to the conclusion that the Romans also decorated their houses in "Colonia Agrippina", here the baths, with this stone.

This rock can be found sporadically on or in historical buildings in the Mediterranean region and beyond. In addition to Italy, examples can be found in Syria, Portugal and England. It occurs very often as an ornament in designed floors ( opus sectile ), but smaller sculptural objects also occur (column capital in Santa Sabina , Rome, from around 1205). Possibly the largest surviving objects are the columned torsos in the Baptistery of San Giovanni in Laterano .

Mosaic floors with many individual elements made from this stone can be seen in Westminster Cathedral in London and in the Church of Santa Maria Maggiore in Rome. Further applications can be found in floor mosaics in Venice, for example in the chapel of Madonna Nicopeia (created before 1500) in the Basilica di San Marco , or as individual elements in the church of Santa Maria dei Miracoli . The rock was mined until the 20th century.

On the road between Krokeai and Stefania you can still find rocks in red and green today. An ancient mining site is located not far from the Alai-Bey locality.

Geology, mineralogy

The rock is described as andesite or dolerite with subsequent metamorphosis , the formation of which lies in the Carboniferous to Permian .

The green silicates epidote and chlorite are mineral components . Light crystal structures consist predominantly of plagioclase . Pyroxenes emerge as dark components . In isolated literature sources, the term serpentinite rock is misleadingly used ( porfido serpentino verde ). In fact, the stone does not contain serpentine minerals .

literature

  • Aschaffenburg Natural Science Association (Ed.): Porphyre (=  messages from the Aschaffenburg Natural Science Museum . Volume 26 ). Helga Lorenz, 2012, ISSN  0939-1924 , p. 188 .
  • Gabriele Borghini (ed.): Marmi antichi. Edizioni de Luca, Rome 2001, ISBN 88-8016-181-4 .
  • Yves Lafond: Krokeai. In: The New Pauly (DNP). Volume 6, Metzler, Stuttgart 1999, ISBN 3-476-01476-2 , Sp. 860.
  • Raymond Perrier: Les roches ornementales. Edition Pro Roc, Ternay 2004, ISBN 2-9508992-6-9 .
  • Monica T. Price: Decorative Stone, the complete sourcebook. Thames & Hudson, London 2007, ISBN 978-0-500-51341-5 .
  • Tudy Sammartini, Gabriele Crozzoli: Stone floors in Venice. Hirmer, Munich 2000, ISBN 3-7774-8570-5 .

Individual evidence

  1. ↑ 3.21.4; also Strabon 8,5,7; Pliny the Elder Naturalis 36,55 and Stephanos of Byzantium .
  2. ↑ Raymond Perrier: Les Roches Ornementales . P. 257.
  3. ↑ Monica T. Price: Decorative Stone. P. 208.
  4. ^ Sammartini, Crozzoli: Stone floors in Venice. Pp. 31, 69.
  5. ^ Gabriele Borghini: Marmi antichi. P. 280.
  6. ↑ a b Monica T. Price: Decorative Stone. P. 206.

Web links

Commons : Verde Antico  - collection of images, videos and audio files