Pentelic marble

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Grave relief of Thraseas and Euandria in the Berlin Collection of Antiquities

Pentelic marble ( Greek  Πεντελικὴ μάρμαρος Pentelikē marmaros , Latin marmor pentelicum , German also: Pentelikon marble ) is a building and decorative stone from Greece and has been of considerable historical importance since ancient times. The stone is one of several important Attic marble types .

Surname

The marble got its name from the Pentelikon mountain range, known today as Pendeli , on which its ancient quarries were built. Pendeli Monastery, on the site of the ancient Pentele demo, carried the original name. The post-antique, old name of the mountain is Brilessos.

Occurrence

The Pentelikon massif with the ancient quarries, view from Nea Penteli

The pentelic marble was extracted on the flanks of the Pentelikon massif on the northeastern outskirts of Athens . The ancient quarries can be found at great heights on the southwest side of the mountain and most of the modern quarries are on its western flank, east of the Athens district of Kifisia / Kephissia. From Athens or the Acropolis , the quarries are easily recognizable when the weather is clear.

An old path leads to the ancient quarries, on which the extracted blocks were transported down by slides. This old path is up to about 700 m above sea level. M. to pursue. The highest ancient quarry is around 1,020 meters above sea level.

Origin, properties, mineralogy

In the ancient mining zone (around 25 quarries), fine layers of chlorite permeate the marble and in this way mark the stratification in the rock. These contact zones are particularly susceptible to later weathering and represent a specific problem for maintenance in numerous ancient buildings. For this reason, heavily weathered components are supplemented or replaced with new pieces.

A white and light gray fine-grain marble comes from the modern quarries. A stratification can be seen in the deposit, which is characterized by gray strip-shaped deposits. The typical grain size is between 0.5 and 1 millimeter, rarely up to 2 millimeters.

According to Richard Lepsius , besides calcite, other minerals can be found in marble . This includes the already mentioned chlorite, as well as the minerals pyrite and quartz as accessory components . The color of the marble from its purest banks is white. The mentioned mineral deposits produce gray and slightly greenish tones. A rather light marble with light gray to gray-green clouds is obtained from the modern mining sites. Due to atmospheric influences, the marble acquires a golden ocher-colored patina after a long period of time, which results from the conversion of the low pyrite content into minerals of the limonite complex and hematite .

The Pentelikon marble, which is currently being mined, is a calcitic fine-grain marble. Its composition is characterized by the following mean values ​​(in percentages by mass): CaO 54.80; MgO 1.55; SiO 2 1.10; Fe 2 O 3 0.14; Al 2 O 3 0.20; K 2 O 0.09; Na 2 O 0.04; MnO 0.02 and carbonate residue 43.05. This means that 98 percent calcite is represented.

The marble deposit is accompanied by phyllites and limestone schists (limestones with a strong directional structure). In the transition zones there are therefore clear green band-shaped deposits in the marble.

history

Considerable amounts of marble were extracted from the Pentelikon mountain in pre-Christian times. During the time of Pericles (5th century BC), marble mining increased in this region. The Greek writer and geographer Pausanias mentioned Pentelic marble in the 2nd century. The Pentelic marble quarrying continued in the time of the Roman Empire . Lepsius estimated the amount extracted at around 400,000 cubic meters. The mining fronts are up to 30 meters high and are partially at right angles to each other. This proves the highly professional technique of ancient marble extraction and, as the mining progresses, repeatedly made rectangular rough blocks possible.

During the reign of Andreas Papandreou , around 1994, the quarries were still because a mining ban was issued. Today the quarry operators largely forego the use of explosives and use the helicoid saw for gentle dismantling .

Use and design

In the following some selected representative application examples for Pentelikon marble are listed. Typical ancient applications are sculptures and architectural parts . In modern times it is used for all conceivable cases of interior and exterior design. For export, the Pentelikon marble, along with some other white marbles from Greece, plays a prominent national role.

Ancient Athens

Modern Athens

Varieties and Competing Marbles

Numerous types of marble from the Greek Attica peninsula and other Mediterranean quarries can be viewed as competing. Hymettic marble, in particular, obtained southeast of Athens, appears as a direct alternative building and decorative stone, because its gray color allowed a conscious contrast to be achieved in architectural applications.

Even in ancient times it was not unusual to use different types of marble in buildings for different architectural elements. In return, no transport distances were spared, especially if the sea route could bridge them cheaply. Important Greek marbles that have found similar uses are the Thassos marble and the Parian marble .

See also

literature

  • C. Colotouros: Marble & Technology , Vol. 2. Athens (no year)
  • A. Dworakowska: Quarries in Ancient Greece . in: Bibliotheca Antiqua 16, Polish Acad. Sciences, Warsaw 1975
  • Norman Herz: Stable isotope applications to problems of classical Greek and Roman marbles: provenance, authenticity and assembly of artifacts . in: Entretiens d'archéologie et d'histoire, Les marbres blancs de Pyrénées. Saint-Bertrand-de-Comminges 1995 ISBN 2-9502446-7-X
  • JG Krünitz: Economic Encyclopedia or general system of rural, domestic and state economics . Volume 84. Berlin 1801
  • G. Richard Lepsius: Greek marble studies . 1890
  • R. Perrier: Marbres de l'Attique, des Cyclades et de Crète . in: Le Mausolée, No. 698, 700, 1994
  • Ludwig Friedrich Wolfram: Complete textbook of the entire architecture; First volume: Doctrine of natural building materials, first section. From natural building materials . Stuttgart (Carl Hoffmann), Vienna (Carl Gerold'sche Buchhandlung) 1833