Verre byzantin et islamiqueByzantine and Islamic Glass
Maria Mossakowska-Gaubert
FREESTONE, Ian C.
Glass Production in Late Antiquity and the Early Islamic Period: a Geochemical Perspective
MAGGETTI, M., MESSIGA, B.
Geomaterials in Cultural Heritage
Geological Society, London, Special Publications 257
Geological Society of London, London, 2006, p. 201-216
[1, 1400]
• Preliminary remarks:
– phenomenon of trade of raw glass;
– single primary workshop could supply many secondary workshops, dispersed over a very large area;
– glass compositions reflect predominantly the primary glassmaking sources, rather than the secondrary workshops in which the objects were made.
• Soda-lime-silica glasses (Antiquity and the Early Islamic Period) – some caracteristics:
– The low-K2O, low-MgO glass is generally used, for most of the first millennium A.D., to the west of the Euphrates, and high-K2O, high-MgO to the est of the Euphrates. A switch from the use of mineral soda to plant ash flux in western regions is observed from the middle of the ninth century A.D.
– low-K2O, low-MgO:
– soda sources:
- evaporitic minerals (especially trona, traditionally known as natron) from Egypt (Wadi Natrun, al-Burnuj - Western Delta) and possibly other locations.
– silica sources:
- pebbles, or, more frequently, sand of siliceous minerals and rocks as vein quartz, chert and quartzite.
– lime sources:
- sand containing calcium carbonate in the form of particles of shell or limestone;
- crushed shell or limestone added to the batch.
– measuring of concentration of strontium and its isotopes ( 87Sr/86Sr) as element to determine the form in which the lime was added to the glass (cf. Freestone et al. 2003):
- glass made with marine biogenic carbonate has ralatively high strontium/calcium ratios,
- glass made with limestone inland sand has low strontium/calcium ratios.
– high-K2O, high-MgO:
– soda sources:
- ash produced by burning halophytic plants, for exemple ‘Salicornia’ and ‘Salsola’, from semi-arid and coastal environments.
– silica sources:
- pebbles, or, more frequently, sand of siliceous minerls and rocks as vein quartz, chert and quartzite.
– lime sources:
- plant ash: limestone-derived stronium detected (from soils parental to the plants that were ashed to make the glass).
– plant ash glass is more complex than glass produced from mineral soda: plant ash carries many minor and trace elements at similar levels of abundance to the source of silica.
– some essays of distincion of plant ash glass groups by anylyses of 87Sr/86Sr and δ18O distribution.
• Recycling of old glass may be recognized by the presence of elevated transition metals (analyses of trace element composition).
• Chemical analyses: K2O, MgO, CaO, Sr, 87Sr/86Sr, Al2O3, MnO, FeO, δ18O; trace elements: Ga, Rb, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Tr.
– phenomenon of trade of raw glass;
– single primary workshop could supply many secondary workshops, dispersed over a very large area;
– glass compositions reflect predominantly the primary glassmaking sources, rather than the secondrary workshops in which the objects were made.
• Soda-lime-silica glasses (Antiquity and the Early Islamic Period) – some caracteristics:
– The low-K2O, low-MgO glass is generally used, for most of the first millennium A.D., to the west of the Euphrates, and high-K2O, high-MgO to the est of the Euphrates. A switch from the use of mineral soda to plant ash flux in western regions is observed from the middle of the ninth century A.D.
– low-K2O, low-MgO:
– soda sources:
- evaporitic minerals (especially trona, traditionally known as natron) from Egypt (Wadi Natrun, al-Burnuj - Western Delta) and possibly other locations.
– silica sources:
- pebbles, or, more frequently, sand of siliceous minerals and rocks as vein quartz, chert and quartzite.
– lime sources:
- sand containing calcium carbonate in the form of particles of shell or limestone;
- crushed shell or limestone added to the batch.
– measuring of concentration of strontium and its isotopes ( 87Sr/86Sr) as element to determine the form in which the lime was added to the glass (cf. Freestone et al. 2003):
- glass made with marine biogenic carbonate has ralatively high strontium/calcium ratios,
- glass made with limestone inland sand has low strontium/calcium ratios.
– high-K2O, high-MgO:
– soda sources:
- ash produced by burning halophytic plants, for exemple ‘Salicornia’ and ‘Salsola’, from semi-arid and coastal environments.
– silica sources:
- pebbles, or, more frequently, sand of siliceous minerls and rocks as vein quartz, chert and quartzite.
– lime sources:
- plant ash: limestone-derived stronium detected (from soils parental to the plants that were ashed to make the glass).
– plant ash glass is more complex than glass produced from mineral soda: plant ash carries many minor and trace elements at similar levels of abundance to the source of silica.
– some essays of distincion of plant ash glass groups by anylyses of 87Sr/86Sr and δ18O distribution.
• Recycling of old glass may be recognized by the presence of elevated transition metals (analyses of trace element composition).
• Chemical analyses: K2O, MgO, CaO, Sr, 87Sr/86Sr, Al2O3, MnO, FeO, δ18O; trace elements: Ga, Rb, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Tr.
analyses chimiques chemical analyses bloc de verre brut lump of raw glass débris d'un four debris from a furnace natron-cendre natron-ash plaque de verre slab of glass
| Chypre Cyprus | Maroni Petrera | consommation | |
| Egypte Egypt | Ashmounein Ashmunein | production | |
| Sinaï Nord North Sinai | consommation | ||
| Grande-Bretagne Great Britain | Jarrow | consommation | |
| Leicester | consommation | ||
| Irak Iraq | Nineveh | consommation | |
| Israël Israel | Arsuf (Apollonia) | production | |
| Banias | production | ||
| Bet Eliʿezer (Hadera) | production | ||
| Bet Sheʾan (Nysa - Scythopolis) | production | ||
| Bet Sheʿarim | production | ||
| Liban Lebanon | Tyr Tyre | production | |
| Oman Oman | Ra’s al Hadd | consommation | |
| Syrie Syria | Raqqa | production |
Version 5, données dudata date 30 janvier 2013January 30th 2013