Pseudo-Aristotle, writing some time from the seventh to the ninth century A.D., was the first to define clearly the three leading varieties of the corundum gems (yakut) as the same mineral substance, and differing only in color. These are the ruby, the Oriental topaz (jacinthus citrinus) and the sapphire. Instead of according different medicinal or talismanic virtues to these three precious stones, this writer states that each and all of them, when set in rings or worn suspended from the neck, protected the wearer from danger in epidemics, gave him the honor and good will of his fellow-men, and also the privilege of having his petitions accorded.[[694]]
The great Athenian comic poet, Aristophanes (c. 448–c. 385), makes Strepsiades, one of his characters in the “Clouds,” assert to Socrates that he knows of a stone having the virtue of saving him from the payment of a claim of five talents, for which suit has been brought against him. This stone, called ὓαλος in Greek, was to be found in the stock of those who dealt in medicines; it was transparent and with it fire could be kindled. The philosopher, although he knows the stone well enough, fails to see how it could be made to help the defendant in a suit at law, and asks Streposiades what he proposes to do with it. The latter is not at a loss for an answer and declares that when the clerk proceeds to write down the charge on his waxen tablet, he, Streposiades, will hold the stone in the sun’s rays so that its beam of light will fall upon the tablet and melt the wax, thus quite literally “wiping out the charge.”[[695]]
Rock-crystal was so highly prized in Roman times that one of the greatest treasures preserved in the Capitol was a mass of this stone, weighing fifty pounds, that had been dedicated by Livia, wife of Augustus Cæsar. Vessels of great size were also made from this material, one of the largest being a bowl owned by Lucius Verus, the colleague of Marcus Aurelius, the dimensions of which were so great that the stoutest toper of the time could not empty it at a single draught. If we can trust a statement of Mohammed Ben Mansur, the Arabs and Persians of a later age must have far surpassed the Romans in the size of their crystal vessels, for he says that a Mauritanian merchant owned a basin of rock-crystal within which four men could seat themselves at the same time. It is true that this basin was composed of two pieces of the material.[[696]]
The Chinese word for crystal, ching, was originally represented by the symbol
; that is, three suns, an attempt to figure the refraction and dispersion of light by the crystal.[[697]] The soui che stone of the Chinese which is said to quench thirst if it be placed in the mouth, is almost certainly rock-crystal, for the Chinese, in common with the ancient Greeks and Romans, believed this substance to be a transformation of water, a kind of fossil ice. A similar power was attributed by Pliny to one of the varieties of agate.[[698]]
Labrets of quartz are used in Central Africa and we have a very interesting description by M. A. Lacroix regarding these ornaments as worn by the natives of a part of the French possessions. In the land of the Bandas the natives highly prize a piece of rock-crystal so shaped that it can be introduced into the lower lip. This usage is confined to the basins of the Ombella, the Kemo and the Tomi, affluents of the Oubanghi.
The following description of the labrets was communicated to M. Lacroix by M. Lucien Fourneau, Administrator of the Colonies:
These objects, called baguérés, consist of hyaline quartz, perfectly transparent; they are very regularly cut, and measure from four to seven cm. (two to three inches) in length. Some have the form of a very elongated and pointed cone, without any protuberances, the greatest diameter being about one cm. (about half an inch); the others, thinner and sharper, have at the base a rim destined to hold them in place; in all cases a pad of thread constituting a kind of permanent plug, assures and completes their stability. Some women wear as many as three of these singular ornaments, thrust, point downwards, into the same lip.
The most regular quartz crystals are selected, and these are chipped off and roughly shaped by blows struck with a hard substance; the quartz is then set in a wooden handle, and the final shaping and polishing are accomplished by friction upon a round slab of quartzite or sandstone. These slabs show grooves along which the crystals have been rubbed. On an average the time required is four or five days of five hours. The completed ornament is valued at nine pounds of red wood worth about $1.20; sometimes one can be secured for three chickens, worth sixty cents.[[699]] Those who cannot afford quartz labrets substitute wood, glass, or pewter. M. Lacroix draws our attention to the fact that a study of the processes employed in shaping and polishing these pieces of quartz is of great importance for the elucidation of the methods in use during the Stone Age.[[700]]