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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
BOOK VI
117
gem aegyptilla has sard-red and black veins through a white stone. Paederos11 has four intermingled colors, white, purple, copper-red and golden yellow. Four distinct colors are found in eupetalos, blue, flame-red, vermillion and apple-green. Hexacontalithos and panchros have many colors.
Gems, especially transparent gems, have many different types of flaws. Some flaws have a color similar to smoke, clouds, shadows, etc. Some have a solid body similar to scales, hairs, salt, dots, shavings, lead rust, iron rust, rust and hidden ulcers. Just as the clear blue of the heavens may be marred when a black, white or streaked cloud crosses it, in the same fashion the beauty of a gem is marred when it contains a smoky or shad­owy flaw, is lightened by a white or cloudy area or is disfigured by dark spots. When they are tinted with a smoky flaw they lose their transpar­ency and brilliancy. Transparent chrysolilhos is often smoky and the Greeks call this and the jaspis which is not transparent capnias (καπνίας). Shadows and clouds are only found in transparent gems. Shadows have a dark color, clouds a white or spotted color. When these flaws occur the gem loses its true color. These flaws may be inside the gem or appear to lie on the edge. They may darken the stone as is common with quartz and some smaragdus or whiten it as in the case of other smaragdus. They may spot the stone as in some quartz. In some stones the flaws may have the same exotic color as the gem in which they occur. Scales appear to be irregularities; hairs look like cracks. Dots of an alien color are called "salt" because of the similarity to white mica. Points have variable colors. "Salt" is conspicuous in quartz, points in sapphire and certain crystals. Any of these flaws may be harder or softer than the rest of the gem. The points which are called "drops" and "stars" we will not regard as flaws since the golden points that sparkle in lapis-lazuli are highly prized as are the golden "drops" that sparkle in sandastros. Shavings do not have an alien color. Chrysolilhos, especially that from Arabia, is sometimes filled with shavings according to Pliny. When they are white they differ from "salt" in being much smaller. Iron rust has an iron color; rust, red; lead, a lead color. Pliny writes that the smaragdus from Athens frequently contains lead rust since the lead color can be seen in the sun. They call a gem ulcerous when it is so filthy that the interior seems to be filled with corrupt material. If the flaws occur on the surface of a gem they can be concealed by smearing some substance over them or they can be removed by engraving but when they occur within the body of the gem they can neither be concealed nor cut away. For that reason gems that contain such objectionable flaws are neither engraved or cut further. If a sapphire contains a point within the crystal it is valueless to the gem cutter. The Greeks call these stones κίντρον. On the other hand beryllus is per-
• Paederos is a general term for opals and other gems showing a play of colors. The name is also given to purple amethyst.
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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