ORICHALCUM, or AURICHALCUM, a metallic substance resembling gold in colour, but very inferior in value. It was well known to the Romans, who often took advantage of its resemblance to gold; for some sacrilegious characters, who could not resist the temptation of taking gold from temples and other public places, chose to conceal their guilt by replacing it with orichalcum. It was thus that Julius Cæsar acted when he robbed the capitol of three thousand pounds weight of gold; in which he was followed by Vitellius, who despoiled the temples of their gifts and ornaments, and replaced them with this inferior metal. It has been a matter of dispute with philosophers and others, what the composition of this metal could be, or how it was procured; it is probable, at least, that it was analogous to our brass, if not wholly the same with it.
The Romans were not only in possession of a metallic
substance, called by them orichalcum, and resembling gold in colour, but they knew also the manner of making it; and the materials from which they made it were the very same with those from which we make brass. There are, indeed, authors of great repute who think very differently, and consider the art of making brass as an invention wholly modern. Thus M. Cronstedt does not think it just to conclude from old coins and other antiquities, that the making of brass was known in the most ancient times; and the authors of the French Encyclopédie assure us that our brass is a very recent invention. It appears, however, from Pliny (Nat. Hist. lib. xxxiv. § 2), and from the concurring testimony of other writers, that orichalcum was not a pure or original metal; but that its basis was copper, which the Romans changed into orichalcum by means of cadmia, a species of earth which they threw upon the copper, and which it absorbed. It has indeed been contended that the cadmia of Pliny was native arsenic; an opinion which scarcely merits confutation, but which must appear extremely groundless, when we reflect that it is impossible to make either brass or copper from arsenic, and that Pliny expressly calls the substance from which brass was made a stone. The testimony of Ambrose bishop of Milan in the fourth century, and of Primasius bishop of Adrumetum, in Africa, in the sixth, and of Isidorus bishop of Seville in the seventh, all seem to confirm Pliny's account. We may therefore safely conclude, that the Romans knew the method of making brass by mixing cadmia or calamine with copper. Yet it is probable they were not the inventors of this art, but borrowed it from some other country. It appears from a variety of testimonies that brass was made in Asia, in a manner similar to that employed at Rome; and a variety of places are mentioned where it was commonly made. It is supposed by some that in India, as well as in other parts of Asia, it was made in the remotest ages.
With respect to orichalcum, it is generally supposed that there were two sorts of this metal, one factitious, and the other natural. The factitious, whether we consider its qualities or its composition, appears to have been the same with our brass. As to the natural orichalcum, there is no impossibility in supposing that copper ore may have been so intimately blended with an ore of zinc, or of some other metallic substance, that the compound, when smelted, might yield a mixed metal of a paler hue than copper, and resembling the colour of gold or of silver.
We know of no country in which orichalcum is found at present; nor was it anywhere found in the age of Pliny, who does not seem to have known the country where it had ever been obtained. He admits, indeed, that it had been formerly dug out of the earth; but it is remarkable, that in the very passage where he mentions by name the countries most celebrated for the production of different kinds of copper, he only says in general, concerning orichalcum, that it had been found in other countries, but without specifying any particular country. Plato acknowledges that orichalcum was a thing only talked of even in his time; it was then nowhere to be met with, although in the island of Atlantis it had been formerly extracted from the mine. The Greeks were in possession of a metallic substance called orichalcum before the foundation of Rome. It is mentioned by Homer and by Hesiod, and by both of these poets in such a manner as shows that it was then held in great esteem. Other ancient writers have expressed themselves in similar terms of commendation; and it is principally from the circumstance of the high reputed value of orichalcum that authors have been induced to suppose that the ancient metal of this name was a natural substance, very different from the factitious one in use at Rome, and probably in Asia, and which, it has been shown, was in no respect different from our brass.
But this conclusion cannot be validly deduced from their
commodities upon orichaleum; for, at whatever time the method of making it was first discovered, its novelty and scarcity, joined to its utility, would enhance its value; at least there can be no absurdity in supposing, that when first introduced it was greatly prized, even though it be granted that it possessed no other properties than such as appertain to brass.
With respect to the etymology of the word there exists great diversity of opinions. Those who write it aurichalum think it is composed of the Latin word aurum, gold, and the Greek χάλκος, brass or copper. But the most general opinion is that it is composed of ὄρος, a mountain, and χάλκος, brass, alluding perhaps to its being found in mountains or mountainous countries.