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Athena becomes even more human in response to changing attitudes about representation of the human form in Greek art. There was a drastic change in the fabric of the coins, as the flans became broader and thinner, and the relief much lower. C., reflects a transition from the Classical to the Hellenistic period of Greek art and coinage. The dating of Athenian coinage of the third century B. The “New Style” owls reflected contemporary attitudes about both coinage and art.

Athena and her owl are marked by almost cartoonish qualities in both appearance and proportion. Whereas the “old” Athenian tetradrachms tended to weigh somewhere in the neighborhood of 17.00-17.50 g., the new style owls fall comfortably within the 16.25-16.95 g. The last of the Athenian owls were minted sometime during the middle of the first century B.The other two of the coins under consideration in Part I were supplied by The American Numismatic Society. Newell and the other officers of the Society I am indebted for encouragement and advice. Allen of the Department of Metallurgy of Columbia University I am extremely grateful for his painstaking work in photographing the many different structures met with in this examination. The upper half is the copper core, the lower part the fusible metal mounting is medium. close plating by means of tin as a soldering medium. In the same way the copper and silver of the eutectic mixture contained 8½% and 9% of the other in solid solution For example, sterling silver 925 fine (92.5% of silver, 7.5% of copper) at ordinary temperatures consists of grains of silver with about 1% of copper in solid solution, the excess copper being found as tiny flakes precipitated in the cleavage planes and at the boundaries of the silver crystals. the solubility is only 8% of copper, leaving 2% undissolved. The coins could be dipped only by means of a tong- or tweezer-instrument or by being fastened on a wire.Most of these specimens had been carefully cut into halves by Dr. One each of these respective halves was mounted in the manner hereinafter described. were mounted in small brass cups filled with fusible metal (bismuth, 4; lead, 2; tin, 1; and cadmium, I) melting at about 75° C. The dark-etching band consists of white patches of the copper-silver eutectic, black areas (holes) where the carbonate has etched out, while the intermediate grayish area is oxidized copper. Shows the details of structure of the coating; patches of the copper-silver eutectic surround irregular grains of oxide or carbonate at the outside while veins of the eutectic have penetrated around the copper grains at the inner surface. The white patches of the eutectic are surrounded by oxide of copper which originally consisted of excess copper crystals; the coating contains less silver than the eutectic alloy. This may be due to quenching the completed coin before the eutectic was completely solid, or to the presence of some other constituent such as tin. To the eye one spot on the edge seems to show a lap or fold. A copper blank was taken and two pieces of silver foil were burnished over it. The greater the copper content the more readily does silver corrode as shown by the new silver coinage of Great Britain which is only 50% silver (500 fine). In each such case there must be places on the blank where the instrument or the wire would touch and be inaccessible to the plating." "There are a considerable number of methods of covering base metals with gold or silver, which are no longer known, since the galvanic method has come so generally into use, such as the so-called hot-gilding—a considerable number of methods through smelting or by means of 'cold-plating', yet because of the technical ignorance of the ancients, none of these need to be considered." "Opposed to this, the following methods appear relatively simple; the melting temperature of silver (and also gold) lies below that of copper (with fine silver the difference constitutes 130 degrees, with silver-alloys, correspondingly more).Knowing the wonderful results to be obtained with the metallographic microscope, especially after etching, I offered to make a metallographic examination of any samples he cared to submit. A preliminary examination was made of a couple of specimens which showed clearly that the silver coating was stuck to the copper core by means of an alloy of silver and copper with a low melting point—in other words, the alloy containing 72% silver and 28% copper, melting and freezing at 778° C., called the eutectic alloy, or, in the trade, pure silver solder. Another small patch is in the midst of the copper oxide. On the right the copper core is badly oxidized while on the left there is a void where the soft copper carbonate has fallen out. The silver surface is pitted as if corroded, and resembles No. The coating was originally base silver, consisting of dendrites and grains of copper surrounded by the copper-silver eutectic. The corrosion of the copper core is very deep, while the coating consists of grains or dendrites of copper oxide (or carbonate) in a matrix of the copper-silver eutectic. The coin looks like silver but in places has a fine pitted appearance. These have not yet been determined with extreme accuracy, but are approximately as given. Hence our 50% silver dendrites, 50% eutectic alloy does not have only ½% Cu in solid solution in the silver. Part III entitled Nummi Subaerati reads as follows : "A problem, the solution of which has caused much racking of brains is the manufacture of the so-called 'plated' coins, which consist of a core of base metal (copper, iron) coated with thin silver (or gold? This plating is found especially in Roman denarii of the republic and early empire.The examination was complicated by the presence of more or less corrosion of the copper core beneath the silver coating, but enough uncorroded areas were found to permit exact determinations. The silver is attached to the copper by irregular patches of the eutectic alloy. Shows practically no oxidation of the copper core which it attached to the silver by a thin layer of the eutectic alloy. Shows the copper core above, next a layer of oxide and a hole which was carbonate, followed by a thick patch of the eutectic passing into the silver coating. The copper grains and dendrites have for the most part become copper oxide and the structure shows up without etching. This is another case where the coating was not silver, but the copper-silver alloy with less silver than the eutectic, say approximately silver 35, copper 65 per cent. The central zone is copper oxide with a few holes originally of copper carbonate. It was mounted whole and filed down well below the outer skin. Under the microscope the core has all the appearance of pure silver, but at the surface it has a peculiar corroded appearance. Such a structure is very similar to that of corroded sterling silver or standard silver 900 fine, in which the copper has become oxidized at the surface. The interior is bright and clean except for one or two small holes. In the first place, the original silver crystals have a composition lying somewhere between and copper begins to separate out, mainly at the crystal boundaries. Mommsen* has established that these were not made by counterfeiters, but that they were an official coinage of a fiduciary nature.

Athena and her owl are marked by almost cartoonish qualities in both appearance and proportion. Whereas the “old” Athenian tetradrachms tended to weigh somewhere in the neighborhood of 17.00-17.50 g., the new style owls fall comfortably within the 16.25-16.95 g. The last of the Athenian owls were minted sometime during the middle of the first century B.The other two of the coins under consideration in Part I were supplied by The American Numismatic Society. Newell and the other officers of the Society I am indebted for encouragement and advice. Allen of the Department of Metallurgy of Columbia University I am extremely grateful for his painstaking work in photographing the many different structures met with in this examination. The upper half is the copper core, the lower part the fusible metal mounting is medium. close plating by means of tin as a soldering medium. In the same way the copper and silver of the eutectic mixture contained 8½% and 9% of the other in solid solution For example, sterling silver 925 fine (92.5% of silver, 7.5% of copper) at ordinary temperatures consists of grains of silver with about 1% of copper in solid solution, the excess copper being found as tiny flakes precipitated in the cleavage planes and at the boundaries of the silver crystals. the solubility is only 8% of copper, leaving 2% undissolved. The coins could be dipped only by means of a tong- or tweezer-instrument or by being fastened on a wire.Most of these specimens had been carefully cut into halves by Dr. One each of these respective halves was mounted in the manner hereinafter described. were mounted in small brass cups filled with fusible metal (bismuth, 4; lead, 2; tin, 1; and cadmium, I) melting at about 75° C. The dark-etching band consists of white patches of the copper-silver eutectic, black areas (holes) where the carbonate has etched out, while the intermediate grayish area is oxidized copper. Shows the details of structure of the coating; patches of the copper-silver eutectic surround irregular grains of oxide or carbonate at the outside while veins of the eutectic have penetrated around the copper grains at the inner surface. The white patches of the eutectic are surrounded by oxide of copper which originally consisted of excess copper crystals; the coating contains less silver than the eutectic alloy. This may be due to quenching the completed coin before the eutectic was completely solid, or to the presence of some other constituent such as tin. To the eye one spot on the edge seems to show a lap or fold. A copper blank was taken and two pieces of silver foil were burnished over it. The greater the copper content the more readily does silver corrode as shown by the new silver coinage of Great Britain which is only 50% silver (500 fine). In each such case there must be places on the blank where the instrument or the wire would touch and be inaccessible to the plating." "There are a considerable number of methods of covering base metals with gold or silver, which are no longer known, since the galvanic method has come so generally into use, such as the so-called hot-gilding—a considerable number of methods through smelting or by means of 'cold-plating', yet because of the technical ignorance of the ancients, none of these need to be considered." "Opposed to this, the following methods appear relatively simple; the melting temperature of silver (and also gold) lies below that of copper (with fine silver the difference constitutes 130 degrees, with silver-alloys, correspondingly more).Knowing the wonderful results to be obtained with the metallographic microscope, especially after etching, I offered to make a metallographic examination of any samples he cared to submit. A preliminary examination was made of a couple of specimens which showed clearly that the silver coating was stuck to the copper core by means of an alloy of silver and copper with a low melting point—in other words, the alloy containing 72% silver and 28% copper, melting and freezing at 778° C., called the eutectic alloy, or, in the trade, pure silver solder. Another small patch is in the midst of the copper oxide. On the right the copper core is badly oxidized while on the left there is a void where the soft copper carbonate has fallen out. The silver surface is pitted as if corroded, and resembles No. The coating was originally base silver, consisting of dendrites and grains of copper surrounded by the copper-silver eutectic. The corrosion of the copper core is very deep, while the coating consists of grains or dendrites of copper oxide (or carbonate) in a matrix of the copper-silver eutectic. The coin looks like silver but in places has a fine pitted appearance. These have not yet been determined with extreme accuracy, but are approximately as given. Hence our 50% silver dendrites, 50% eutectic alloy does not have only ½% Cu in solid solution in the silver. Part III entitled Nummi Subaerati reads as follows : "A problem, the solution of which has caused much racking of brains is the manufacture of the so-called 'plated' coins, which consist of a core of base metal (copper, iron) coated with thin silver (or gold? This plating is found especially in Roman denarii of the republic and early empire.The examination was complicated by the presence of more or less corrosion of the copper core beneath the silver coating, but enough uncorroded areas were found to permit exact determinations. The silver is attached to the copper by irregular patches of the eutectic alloy. Shows practically no oxidation of the copper core which it attached to the silver by a thin layer of the eutectic alloy. Shows the copper core above, next a layer of oxide and a hole which was carbonate, followed by a thick patch of the eutectic passing into the silver coating. The copper grains and dendrites have for the most part become copper oxide and the structure shows up without etching. This is another case where the coating was not silver, but the copper-silver alloy with less silver than the eutectic, say approximately silver 35, copper 65 per cent. The central zone is copper oxide with a few holes originally of copper carbonate. It was mounted whole and filed down well below the outer skin. Under the microscope the core has all the appearance of pure silver, but at the surface it has a peculiar corroded appearance. Such a structure is very similar to that of corroded sterling silver or standard silver 900 fine, in which the copper has become oxidized at the surface. The interior is bright and clean except for one or two small holes. In the first place, the original silver crystals have a composition lying somewhere between and copper begins to separate out, mainly at the crystal boundaries. Mommsen* has established that these were not made by counterfeiters, but that they were an official coinage of a fiduciary nature. With regard to these, the following notes are offered: The obvious question with all of these finds is whether they represent modern losses by tourists and collectors, or if they were instead ancient losses made during the Roman period or even before.