door r+bke » vr 20 okt 2006, 13:51
Natron - Mummy Mineral
Ancient Egyptians were famous for their perfection of the art of mummification. A key ingredient in the process is a mineral called natron, whose preservative properties rival those of salt.
Natron is a sodium carbonate (Na2CO3.10H20) which crystallizes in the monoclinic system. It commonly forms clear, white, yellow or gray crusts of granular or columnar crystals. It dissolves in water and also absorbs water readily, making it an excellent desiccant. Natron is found in quantity naturally in the beds of several Egyptian playa lakes. It forms when lake water of a particular composition evaporates, as it would happen periodically in the hot Egyptian climate. Natron does not form from the evaporation of sea water, where most of the sodium present would be tied up as halite (NaCl). Its preservative qualities must have been immediately apparent from its effects on wild life which drowned in these lakes. At several Egyptian localities ( Wadi Natrun and Behiera in the Libyan desert and El Kab in Upper Egypt) the natron has accumulated in beds and incrustations several feet thick. This material has been mined and traded from these localities for thousands of years. Egyptian writings as old as the reign of Ramese III (1198-1166 B.C.) refer to these deposits. There is some evidence that the natron was artificially precipitated by isolating shallow basins of lake water for faster evaporation.
The natron was a preferred material for mummy purification and preservation. Natron is superior to salt as a drying agent because it chemically attacks and destroys grease and fat. It is found not only in tombs and in pits with other discarded embalming materials, but also as nodules and residues in the mummies themselves. There is some debate over the method in which the natron was used. It may have been used in a way similar to the method for the preservation of fish. Dry natron would be sprinkled over the body, perhaps with sawdust, or spread with linen clothes. Other archeologists believe the body was immersed in vats containing a natron solution. Such a wet method would however be odiferous, accelerate putrefaction and thus be counterproductive to the preservation of the body. A dry body would also be more readily bandaged as well as more amenable to the attachment of amulets and other jewelry.
Although mummification has supernatural trappings, its basis is rooted in simple chemistry and processes as mundane as fish preservation. It also is another example of a technology born out of observations of the properties and effects of rare minerals.
Natron - Mummy Mineral
Ancient Egyptians were famous for their perfection of the art of mummification. A key ingredient in the process is a mineral called natron, whose preservative properties rival those of salt.
Natron is a sodium carbonate (Na2CO3.10H20) which crystallizes in the monoclinic system. It commonly forms clear, white, yellow or gray crusts of granular or columnar crystals. It dissolves in water and also absorbs water readily, making it an excellent desiccant. Natron is found in quantity naturally in the beds of several Egyptian playa lakes. It forms when lake water of a particular composition evaporates, as it would happen periodically in the hot Egyptian climate. Natron does not form from the evaporation of sea water, where most of the sodium present would be tied up as halite (NaCl). Its preservative qualities must have been immediately apparent from its effects on wild life which drowned in these lakes. At several Egyptian localities ( Wadi Natrun and Behiera in the Libyan desert and El Kab in Upper Egypt) the natron has accumulated in beds and incrustations several feet thick. This material has been mined and traded from these localities for thousands of years. Egyptian writings as old as the reign of Ramese III (1198-1166 B.C.) refer to these deposits. There is some evidence that the natron was artificially precipitated by isolating shallow basins of lake water for faster evaporation.
The natron was a preferred material for mummy purification and preservation. Natron is superior to salt as a drying agent because it chemically attacks and destroys grease and fat. It is found not only in tombs and in pits with other discarded embalming materials, but also as nodules and residues in the mummies themselves. There is some debate over the method in which the natron was used. It may have been used in a way similar to the method for the preservation of fish. Dry natron would be sprinkled over the body, perhaps with sawdust, or spread with linen clothes. Other archeologists believe the body was immersed in vats containing a natron solution. Such a wet method would however be odiferous, accelerate putrefaction and thus be counterproductive to the preservation of the body. A dry body would also be more readily bandaged as well as more amenable to the attachment of amulets and other jewelry.
Although mummification has supernatural trappings, its basis is rooted in simple chemistry and processes as mundane as fish preservation. It also is another example of a technology born out of observations of the properties and effects of rare minerals.
