Thassos marble
Thassos marble, ca.450 BC. BC, found in Limenas (Musée du Louvre , Paris, France)
The Thassos marble (English: Thassos Marble , also Limenas White ) is on the Greek island of Thasos dismantled and is one of the most important ancient and modern construction and decorative rocks white color in Europe and Asia Minor. This marble is in its best sorting of pure white color and was already used extensively as marble Thasium in the Roman Empire .
The mining sites are on the island of Thasos , which is located in the northern part of the Aegean Sea . The focus of modern mining is on the quarries in the northeastern island area. In ancient times, quarries were also active on the south coast.
history
The marble quarrying on Thasos has been documented since the 5th century BC. In ancient times, marble was mined near the coast because it was relatively easy to transport it by ship. At that time sarcophagi and statues were made of it. The raw pieces intended for the pillars were dispatched as semi-finished products and made their way to many places in the Roman Empire. The material went, for example, to southern Greece, to buildings on the islands in the Aegean Sea, to regions in the Middle East (Jordan, Egypt) and to North Africa.
The fine to medium-grained, light white dolomite marble from Vathi was preferred for the production of statues, portrait busts, heads, grave steles, reliefs, door frames and sarcophagi. The latter went, among other things, prefabricated in large numbers from Vathi to Rome. It is believed that most of the dolomite marble sculptures made from ancient times to Roman times were made from Vathi marble.
The greater mineral hardness and the better acid resistance of the stone from some quarries, which is caused by its dolomite content, had already been noticed in ancient times. That is why the Italian sculptors later called it Marmo Greco duro (hard Greek marble).
Political upheavals promoted the decline of marble mining in the 17th century. It only came back to life in the late 19th century and has continued into modern times.
In the 20th and 21st centuries, the marble from the island of Thasos, along with other deposits from the areas around Drama and Kavala, is one of the most important export goods and the entire region forms the most important center of modern marble extraction in Greece. About 80 percent of the total Greek marble production comes from here.
Usage and design today
In the Theologos area, three quarries were opened again around 1967. In 1995 there were 17 quarries in the Saliara area and 4 quarries in the Theologos region. The annual production in 1995 was 60,000 m³ dolomite marble and around 4,000 m³ calcite marble.
Raw blocks of considerable dimensions are extracted through careful mining. The world's most valued variety is traded under the special name Snow of Thassos . It is a pure white stone of unusually high reflectivity. This sorting is one of the most important national export items in Greece. The Thassos marble is used for interior decorations and art objects of all kinds. Representative staircases, bathrooms and swimming pools are typical. Table tops, wall coverings, pillars, lamp bases, decorative architectural parts and designer objects are also common. Mass products such as tiles, slabs, bathroom furnishings, monuments and works of art are also exported. Large unprocessed blocks are mainly sent to China and Albania, blocks of inferior quality are marketed for coastal and pier protection, and fine material is shipped as white chippings or gravel.
Quarries
There are ancient quarries and those operated in 2008: There are important ancient quarries
- near Aliki, on the outer coast of the peninsula
- at Cape Vathi
- south of Astris, at Cape Salonikios
- at Cape Babouras
- southeast of Thasos City
There are important active quarries
- on the hilltops west of the Panagia settlement, north slope from Profitis Ilias mountain
- south of Thásos / Limenas
- above the Saliara bay, on the Kastania ridge
- above the settlement Chrisi Ammoudia, on the ridge of Livadakia
Origin, properties, mineralogy
The emergence of the later marble deposit goes back to a sedimentation of lime in the time of the Jurassic and Cretaceous . During the Tertiary period , several phases of tectonic activities followed south of the Rhodope Mountains, accompanied by enormous compressions. This led to rock metamorphosis in the regions affected. The origin of the marble is dated to a phase beginning in the Oligocene to the Miocene . The island belongs to the Rhodope massif and is still on the Eurasian plate near the Aegean plate .
The crystal size ( grain size ) of dolomitic marble can vary and is typically between 0.6 and 2 millimeters. Accessory minerals such as muscovite and quartz occur in some mining sites .
Small cavities that can reach a maximum size of a few millimeters are typical of the rock .
Some ancient quarries produced a calcitic marble. The grain size here reaches 2 to 3 millimeters.
The Thassos marble, which is currently being mined, is a dolomitic , coarse-grained marble. Its composition can be derived from the following mean values (in percent by mass):
CaO 31.60,
MgO 19.20,
SiO 2 0.20,
Fe 2 O 3 <0.05,
Al 2 O 3 <0.05,
K 2 O <0.01,
Na 2 O <0.01,
MnO <0.01,
carbonate residue 46.60.
Varieties and Competing Marbles
Various grades are obtained from the quarries on Thasos. These have their own names in the trade and in this way allow a distinction to be made between purity classes. Specifically, these are:
Snow of Thassos (ΘΑΣΟΥ,), pure white flawless batch
Thassos A1 (ΘΑΣΟΥ ΛΕΥΚΟ), high white
Thassos A2 , very light gray cloud or stripes
Thassos A3 , clearly gray structure
Thassos A4 , predominantly gray structure
Some Greek companies use different names for the differentiation of varieties. All of these distinctions represent optical manifestations of nature and are not quality criteria in the technical sense. In all grades, the mentioned small voids can occur within the crystal structure.
Yellowish discoloration due to iron minerals is possible with low-priced varieties and can be intensified by external influences.
Another type of natural stone that is mined on Thassos is known under the two names Thassos Limenas White or Prinos (ΠΡΙΝΟΣ). Their structure shows inclusions of larger, clear and eye-shaped calcite crystallites. The degree of whiteness is not that high here.
Thassos marble, crystalline structure of a fracture surface
Ancient quarry near Aliki on Thasos, mining areas are already flooded by the sea
View of today's quarries with loading point, east coast
Shipping of marble chippings in the bay of Saliara
See also
- Mining and metal extraction on the island of Thasos (history of marble mining)
literature
- C. Colotouros: Marble & Technology, Vol. 2 . Athens (no year)
- John J. Herrmann Jr./ Vincent Barbin: The Exportation of Marble from the Aliki Quarries on Thasos: Cathodoluminescence of Samples from Turkey and Italy . In: American Journal of Archeology , Vol. 97 (1993), No. 1 (January), pp. 91-103, ISSN 0002-9114
- Friedrich Müller : The international natural stone index for the current market. INSK compact , sheet 81.3 (loose-leaf edition)
- Monica T. Price: Decorative Stone, the complete sourcebook . Thames & Hudson, London 2007, ISBN 978-0-500-51341-5 .
- Raymond Perrier: Les roches ornementales . Édition Pro Roc, Ternay 2004, ISBN 2-9508992-6-9 .
Individual evidence
- ↑ K. Laskaridis: Greek marble through the ages: an overview of geology and the today stone sector . In: R. Přikryl (Ed.): Dimension Stone 2004. New Perspectives for a Traditional Building Material . Taylor & Francis Group, London 2004, p. 68, ISBN 90-5809-675-0 .
- ↑ D. Sokoutis, JP Brun, J. van den Driessche, S. Pavlides: A major Oligo-Miocene detachment in southern Rhodope controlling north Aegean extension . In: Journal of the Geological Society , Vol. 150 (1993), No. 2, pp. 243-246.
- ↑ a b c R. Perrier: roches ornementales. 2004, p. 364
- ^ A b R. Perrier: Marbres de Grèce continentale et du Péloponèse . In: Le Mausolée (No. 642) 1990, pp. 67-85
- ^ N. Epitropou: Southern Thassos. Designation of Geosites - Geoparks, Contribution to Sustainable Developement. Xanthi 2009, ISBN 978-960-98903-3-5 ( Online ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this note. , PDF)
- ↑ C. Colotouros: Marmor & Technologie , Vol. 2. P. 366
