We have already stated, in the Seventh844 Book, who were the first discoverers of gold, as well as nearly all the other metals. The highest rank has been accorded to this substance, not, in my opinion, for its colour, (which in silver is clearer845 and more like the light of day, for which reason silver is preferred for our military ensigns, its brightness being seen at a greater distance); and those persons are manifestly in error who think that it is the resemblance of its colour to the stars846 that is so prized in gold, seeing that the various gems847 and other things of the same tint, are in no such particular request. Nor yet is it for its weight or malleability848 that gold has been preferred to other metals, it being inferior in both these respects to lead—but it is because gold is the only849 substance in nature that suffers850 no loss from the action of fire, and passes unscathed through conflagrations and the flames of the funeral pile. Nay, even more than this, the oftener gold is subjected to the action of fire, the more refined in quality it becomes; indeed, fire is one test of its goodness, as, when submitted to intense heat, gold ought to assume a similar colour, and turn red and igneous in appearance; a mode of testing which is known as “obrussa.”851
The first great proof, however, of the goodness of gold, is its melting with the greatest difficulty; in addition to which, it is a fact truly marvellous, that though proof against the most intense fire, if made with wood charcoal, it will melt with the greatest readiness upon a fire made with chaff;852 and that, for the purpose of purifying it, it is fused with lead.853 There is another reason too, which still more tends to enhance its value, the fact that it wears the least of all metals by continual use: whereas with silver, copper, and lead, lines may be traced,854 and the hands become soiled with the substance that comes from off them. Nor is there any material more malleable than this, none that admits of a more extended division, seeing that a single ounce of it admits of being beaten out into seven hundred and fifty855 leaves, or more, four fingers in length by the same in breadth. The thickest kind of gold-leaf is known as “leaf of Præneste,” it still retaining that name from the excellence of the gilding upon the statue of Fortune856 there. The next in thickness is known as the “quæstorian leaf.” In Spain, small pieces of gold are known by the name of “striges.”857
A thing that is not the case with any other metal, gold is found pure in masses858 or in the form of dust;859 and whereas all other metals, when found in the ore, require to be brought to perfection by the aid of fire, this gold that I am speaking of is gold the moment it is found, and has all its component parts already in a state of perfection. This, however, is only such gold as is found in the native state, the other kinds that we shall have to speak of, being refined by art. And then, more than anything else, gold is subject to no rust, no verdigris,860 no emanation whatever from it, either to alter its quality or to lessen its weight. In addition to this, gold steadily resists the corrosive action of salt and vinegar,861 things which obtain the mastery over all other substances: it admits, too, beyond all other metals, of being spun out and woven862 like wool.863 Verrius tells us that Tarquinius Priscus celebrated a triumph, clad in a tunic of gold; and I myself have seen Agrippina, the wife of the Emperor Claudius, on the occasion of a naval combat which he exhibited, seated by him, attired in a military scarf864 made entirely of woven gold without any other material. For this long time past, gold has been interwoven in the Attalic865 textures, an invention of the kings of Asia.