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Book VIII metals, precious such as gold, platinum, silver

Book VIII metals, precious such as gold, platinum, silver Page of 251 Book VIII metals, precious such as gold, platinum, silver Text size:minus plus Restore normal size   Mail page  Print this page
184
DE NATURA FOSSILIUM
the sky, accompanied by a fiery hissing thus giving warning in two ways. There is a goblet of this type in the temple to Minerva in Lindos, a town of Rhodes. Homer writes that Menelaus wore a ring made of electrum.
The finest mirrors are made from stannum.
In this same fashion, Nature sometimes mixes three metals, for example, gold, silver and copper, and at other times four, silver, copper, tin and bismuth. Having been instructed by Nature we also mix metals in this fashion. Not only does Nature teach us the correct proportions to use in the alloys but we also learn through accidents to imitate Nature. For example, in a fire at Corinth gold, silver and copper were melted together and by good fortune combined in the correct proportions of the three varieties of Corinthian copper. One of these is white and, as Pliny writes, approaches closest to the appearance of silver when that metal is the domi­nant one. Another is as yellow as gold. The third has the three metals in equal proportions. Art and fraud imitate Nature through mixing metal with metal in various proportions. The Greeks call this correct proportion­ing κράματος, the Romans temperatura. Two, three, or more, simple or complex metals may be mixed together. A simple metal may be mixed with a complex, a complex with a simple, two simple with one complex, two complex with one simple, and many simple with one or two complex metals and vice versa. The proper proportion of these metals varies since sometimes a base metal is mixed with a precious metal and vice versa. One should examine every alloy to determine whether it may be of any use at present or at some future time. It may have neither a present nor future use or it may have a future use and be of no present value or it may have a present use and be of no use in the future. Next one should consider what use each may or may not have. It should be examined to determine if it is a fraudulent or artificial alloy. Finally one should deter­mine what name the Greek or Roman writers have given it or if it lacks a name.
First we shall consider gold that is mixed in various proportions. All these alloys lack names except that with one part of silver to four parts of gold which we call electrum. Certain men make a practice of mixing a small quantity of some base metal with a large mass of precious metal, not to make a legitimate alloy but to make a profit. They admit this to be a crime since they do their work in secret. Mention could be made of the fraudulent contractor to whom Hiero of Syracuse gave a contract to make a crown. As he made the crown he substituted silver for some of the gold. This theft was finally detected by Archimedes. On the other hand kings and princes protect the worker who substitutes silver for gold in making coins since they say they have the legal right to make money that is not pure gold. Flavius Vopiscus writes that the Emperor Tacitus, in a speech before the senate, ordered that it be considered a capital crime for any­one to mix copper with silver, silver with gold, or lead with silver, either publicly or privately and offer it for sale as pure metal. This just and good
Book VIII metals, precious such as gold, platinum, silver Page of 251 Book VIII metals, precious such as gold, platinum, silver
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