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Book VI gems: diamond, emeralds, sapphire, topaz, chrysoberyl, carbuncle, jaspis

Book VI gems: diamond, emeralds, sapphire, topaz, chrysoberyl, carbuncle, jaspis Page of 251 Book VI gems: diamond, emeralds, sapphire, topaz, chrysoberyl, carbuncle, jaspis Text size:minus plus Restore normal size   Mail page  Print this page
122
DE NATURA FOSSILIUM
Diamond differs from quartz in hardness. The former is actually so hard that if placed on an anvil and struck with an iron hammer, the hammer and anvil will break before the diamond can be fractured or crushed.10 It will not only withstand the blows of a hammer but also fire. If we are to believe Pliny it will not melt or even glow in the hottest fire. According to Xenocrates it is not fouled in a fire but is purified. Never­theless the exceptional hardness of this remarkable stone can be reduced by placing it in the blood of a male goat or lion, after which it can be broken. When placed in liquid lead in a very hot furnace it will melt. Actually all diamonds are not of the same hardness. Those from Cyprus and the variety siderites are broken by the blow of a hammer and holes can be drilled through them with other diamonds. Pliny writes that he was the first to call these stones "degenerate." The very finest diamonds can destroy the force of lodestone just as the blood of a male goat or lion can reduce the hardness of a diamond. When the diamond is placed next to the iron the lodestone cannot attract it, or if eventually it does attract the iron it is drawn away violently from the diamond. A diamond can de­tect poison and render it harmless. For this reason it has always been highly prized by royalty and therefore has always commanded a high price. It is reported to prevent insanity but this is hard to believe. Finally, gem engravers set broken fragments of diamond in iron and because of the superior hardness use them to engrave all other gems.
Androdamas also forms from a colorless essence. The name, as many believe, comes from its power to subdue the violence of men and to cool anger (ανδρός, man, δάμασν, subduing). It is found in Arabia. With the color and luster of silver it has the appearance of a diamond although it has a different form. It occurs as a cube. Although it may be cubical and without the same properties nevertheless it is today called diamond, a hexagonal mineral.
The following gems are white and multicolored, that is, they change color when inclined just as does a variety of silk cloth when viewed from different directions. The Greeks call these gems paederos, the name being derived from the passionate love of youth, because of its exceptional charm (παιδίον, boy; epos, love). In this group of gems the finest is the opalus. When it is inclined one sees in it the weaker fire of the carbunculus, the gleaming purple of the amethyst, the sea green of the smaragdus, and all of these colors sparkling in an incredible intermixture. Masses are found the size of a hazelnut. It is found only in India and is more valuable than the smaragdus. It is brought to us only rarely. The gem that takes second place is called sangenis by the Indians, Semites by the Egyptians. When inclined this shows the colors copper-red, purple, and wine-yellow. The wine-yellow color always occurs around the outer edge while the purple, according to Pliny, spreads to the yellow and mixes with all the other colors. This gem, pleasing and delightful to the eye, occurs in India,
10 A fallacy widely held in ancient and medieval times.
Book VI gems: diamond, emeralds, sapphire, topaz, chrysoberyl, carbuncle, jaspis Page of 251 Book VI gems: diamond, emeralds, sapphire, topaz, chrysoberyl, carbuncle, jaspis
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