Alum, Roman

Alaun, m. alum. — — von Rocca, roche alum, Roman alum. 

Berg-ader, /. lode, vein, -akademie, /. school of mines, -alaun, m. rock alum, roche alum (Roman alum) alum stone, alumte. beigan, adv. uphill. 

L. alumen, alum) The ancient Greeks and Romans used alum as an astringent and as a mordant in dyeing. In 1761 de Morveau proposed the name alumine for the base in alum, and Lavoisier, in 1787, thought this to be the oxide of a still undiscovered metal. 

Aluminum Sulfate (Alum). Alum, a double sulfate of potassium and aluminum having twelve waters of crystallization, KA1(S0 2 12H20, is the earliest referenced aluminum containing compound. It was mentioned by Herodotus in the fifth century BC. The Egyptians used alum as a mordant and as a medicine the Romans used it for fireproofing. Some alums contain sodium or ammonium ions in place of potassium. 

Romans used a mixture of alum and vinegar on wood. About 200 B.C. 

Aluminium - the atomic number is 13 and the chemical symbol is Al. Although the name was originally called alumium, it was later changed to aluminum. Internationally, the element is referred to as alviminium, to conform with the ium ending of most metallic elements. The name derives from the Latin, alum and alumen for stringent , since the early Romans called any substance with a stringent taste alum. The element was known in prehistoric times. In 1825, the Danish physicist, Hans Christian Oersted, isolated impure aluminium. The pure metal was first isolated by the German chemist Friedrich Wohler in 1827. 

The electrochemical replacement of one metal by another was noticed by Pliny in antiquity. He mentioned that iron looks like copper if it is smeared with vinegar or alum previously ground in a bronze mortar [275], Metal replacement seems to have also been used in the Roman era for tin-plating bronze, as well as underlying the recipes for the preparation of iron surfaces to receive amalgam gilding that are given in the 9th century [276],... 

Aluminum, the most abundant metal in the earth s crust at 8.3%, takes its name from alum, KAIJSO 12 H20, a salt that has been used medicinally since Roman times. In spite of its abundance, the metal nevertheless proved difficult to isolate in pure form. It was such a precious substance in the midnineteenth century, in fact, that aluminum cutlery was sometimes used for elegant dinners, and the Washington Monument was capped by a pyramid of pure aluminum. Not until 1886 did an economical manufacturing process become available. 

In 1702, William Homberg heated borax with iron(n) sulphate and obtained by sublimation a compound he called sedative salt , though it was not a salt but boric acid.94 The boron hydrides, first studied by A. Stock in 1909, have provided a rich source of new chemistry.95 Pliny described a silvery cup, lighter than any known metal, once owned by the emperor Tiberius. Some have speculated that the Romans might have stumbled on aluminium.96 Though alum was known in antiquity, the... 

Synonyms Alum, Alum flour, Alum meal, Aluminite, Aluminum and potassium sulfate, Common alum, Cube alum, Double sulfate of aluminum and potassium, Octahedral alum salt, Potash alum, Potassic-aluminic sulfate, Potassium-aluminum sulfate, Roman alum, Sulfate of aluminum and potassium. 

Like many elements, aluminum s name derives from the Latin because the Roman Empire used two of its naturally occurring minerals, alum (a potassium-aluminum sulfate) and alumina (aluminum oxide). It was isolated in 1825 by H. C. Oersted after decades of suspicion that it existed. 

The Romans first treated wood for fire retar-dancy in the first century a.d. They used solutions of alum and vinegar to protect their boats against fire. In 1820, Gay-Lussac advocated the use of ammonium phosphates and borax for treating cellulosic material. Many of the promising inorganic chemicals used today were identified between 1800 and 1870. Since then, the development of fire retardants for wood has accelerated. Commercially treated wood became available after the U.S. Navy (1895) specified its use in ship construction, and New York City (1899) required its use in buildings over 12 stories tall. Production reached over 65 million board feet in 1943, but by 1964 only 32 million board feet was treated annually.35... 

PYRITES and MARCASITE — are the same, for what the Romans and Greeks called Pyrites the Arabs term Marcasite and Black Zeg. Others call it the Stone of Light, on account of its effects also Marcasite Capporosa, Copper Stone, Chalcitis, Rock Alum in its first signification, etc. All that the Greeks have written concerning Pyrites the Arabs ascribe to Marcasite in their own language. 

During the periods of ancient civilization, there was also some concern for prevention of fire and for flameproofing. It is known that the Egyptians soaked wood in a solution of alum, and that later, the Romans attempted to flameproof their houses and war vessels by dipping the wood in a bath of vinegar and clay. ... 

No one is sure when alum was first used by humans. The ancient Greeks and Romans were familiar with the compound alum. It was mined in early Greece where it was sold to the Turks. The Turks used the compound to make a beautiful dye known as Turkey red. Records indicate that the Romans were using alum as early as the first century bce. 

Although aluminum was one of the last metals to be commercialized, it has been recognized for centuries. Aluminum was first recognized by the Romans as an astringent substance, and they called it alum . By the Middle Ages it was manufactured as alum stone , a subsulfate of alumina and potash. In 1825, Hans C Oersted was able to isolate a few drops of the raw material, and then by 1886 it had patents from both Charles Martin Hall of the United States and Paul-Louis-Toussaint Heroult of France. Aluminum was commercialized in industry by the end of the nineteenth century. 

Roman alum Ordinary alum crystallized In cubes. 

The Romans used the term alumen to denote substances of an astringent taste. One of these was a crystalline substance well known to Geber (died a.d. 765) and the later alchemists, who classed it with the vitriols. This was our alum . 

The concept of fire-retardancy is remarkably old. The Greek historian, Herodotus, in 484-431 BC recorded that the Egyptians imparted fire-resistance to wood by soaking it in a solution of alum (potassium aluminum sulfate) [Browne, 1958]. The Romans added vinegar to the alum for the same purpose. Vitruvius in the first century BC described the natural fire-retardant properties of the larch tree and some military applications of fire retardant materials such as plaster of clay reinforced with hair [Vitruvius, I960]. In 1638, Circa recorded that Italian theaters were painted with a mixture of clay and gypsum (potassium aluminum silicate and hydrated calcium sulfate) to protect them from fire. Wild was issued a British patent in 1735 for his process of treating wood with a mixture of alum, ferrous sulfate and borax (sodium tetraborate decahydrate). And Gay-Lussac in 1821 showed that a solution of ammonium phosphate, ammonium chloride and borax acts as a fire-retardant for wood. 

Chemically related to brazUin are the yellow mordant dyes, luteolin and morin. Both are flavone derivatives whereas the former is obtained from yellow weed or weld (Reseda luteola L.), which grows widely across Europe, the latter comes from dyer s mulberry (Madura tinctoria, syn. Morus tinctorius L.). Alum- and tin-based mordants from luteolin produce a beautiful true yellow on all textile materials. Apart from weld, saffron (Crocus sativus L.) used to be the most important yellow colourant. The ancient Greeks and Romans used the dried stigmas from this species of crocus to obtain crocin, which was absorbed onto textiles with an alum mordant. Like saffron, curcuma (also known as turmeric) serves as a colourant for foodstuffs (e.g. for mustard and curry), and as a somewhat acrid spice in Oriental and South-east Asian cuisine. Curcuma is obtained from the root nodules of, for instance. Curcuma longa L., which is cultivated in plantations in China and the East Indies. 

Alum was used by the Greeks and Romans in medicines and in dying processes. In 1807, Davey proposed the name alumine for the as yet undiscovered metal in alum. Finally, in 1825 Hans Christian Oersted isolated an impure sample of aluminum by heating AICI3 with potassium amalgam and boiling off the mercury at the end of the reduction. 

The alum deposits on the island of Ischia outside Napoli were worked in the 12 century ad, but new applications for alum, such as for instance in the taiming of leather, increased demand so much that alum had to be imported from the Middle East Roman alum workers were active in Syria, and Roman merchants took care of the deliveries to their home provinces. However, everything was changed by Turkish expansion in the 15 century. The Romans had to return home not only to unemployment but also to the task of finding new domestic deposits of alum. In a barren mountain district at Tolfa near Rome they found the same type of vegetation that they... 

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