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Book IX artificially coloring of metals such as gold, silver, copper

Book IX artificially coloring of metals such as gold, silver, copper Page of 251 Book IX artificially coloring of metals such as gold, silver, copper Text size:minus plus Restore normal size   Mail page  Print this page
BOOK IX
199
Europe. As a remedy it cools and is used as an ointment. Women use it for whitening the skin. If drunk it is fatal.
The cerussa called cerussa cinerea by some, plumbarius cinerea by others, is prepared in the following manner. A new earthenware vessel is placed on a charcoal fire and ground cerussa placed in it. It is stirred continuously with a small wooden spoon until it becomes the color of ashes, after which it is removed from the fire.13
There is another material that some Greeks call σάνδυκα and Pliny, following them, calls sandyx. Other Greeks call it φύ/cos because it re­sembles rouge. Vitruvius calls it sandaraca since it has the same color as this mineral (realgar). It is prepared in the following manner. A dish is placed on glowing charcoal and filled with crushed cerussa. This is stirred with a wooden spoon until the entire mass becomes the color of realgar. Vitruvius writes that men learned how to make this material14 by accident and that it is superior to the natural mineral found in mines.
The ocher we call plumbaria is made from lead. This substance was first discovered by chemists and is prepared in the following manner. Lead is placed in an oblong flask and the latter placed in a chemists fur­nace. It is heated until the lead becomes the color of ocher. Painters use this as well as sandyx.
Tin smelters produce a variety of cerussa that is called Spanish White because it is produced by the Spaniards. It is prepared in the following manner. Urine is heated in a flask with an elongated spout, similar to that used in distilling, and tin is added. When the tin is entirely dissolved the urine is decanted. The glutinous mass that remains in the bottom of the flask is dried in the same way as other cerussa, then crushed and sieved. This is used by women to whiten the skin.
Quicksilver refineries produce minium and an artificial minium, each of which is called cinnabaris today. Chemists first discovered these sub­stances by accident. When they threw sulphur on quicksilver in an at­tempt to produce silver or gold they produced this pigment instead. When the quicksilver mines of Betica ceased to produce this pigment minium took its place. It is prepared by placing a large shallow dish on a charcoal fire and placing in it one part of ground sulphur. When the sulphur has melted two parts of quicksilver are added and the mixture stirred rapidly and continuously with a wooden spoon until the two are thoroughly mixed and no quicksilver remains. After cooling the mass is pulverized and the powder placed in a flask with rather a long neck. If the flask is of glass it is coated outside with an inch of mud and, if an earthen­ware flask, the inside is coated with lead or lead oxide. The mouth is then covered and sealed and the vessel placed in a chemists furnace or on an iron tripod over a charcoal fire. It is heated slowly until the sound of the
11 This would be a mixture of lead oxide and basic lead acetate. 14 Red oxide of lead. The natural mineral is called minium.
Book IX artificially coloring of metals such as gold, silver, copper Page of 251 Book IX artificially coloring of metals such as gold, silver, copper
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