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BOOK IX
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199
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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.
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