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176
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DE NATURA FOSSILIUM
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vessel
where it forms a substance they call mercury sublimate. This has
corrosive properties equal to quicklime and will even destroy the
latter. Enough concerning quicksilver.
The Greeks call copper {aes) χαλκοί. It
is found as a native metal not only in its own veins but also in silver
veins. The old writers and even Al-bertus did not know this although
the latter writes that the best and purest is found at Goslar mixed
with all kinds of stones such as marchasita, his name for
pyrite. Actually if it is found mixed with all kinds of stones it is
not pure, much less the purest. It is purified by smelting. I do not
know if copper is found in masses that equal the size of masses of
native silver but small masses occur in different forms, for example,
stalactites, small branches, globular masses, etc. Very thin foils are
found adhering to stones. Native copper often contains small amounts of
silver.
Copper
has a characteristic red color. The finest color is found in the metal
that has been smelted from veins. However the color varies. Some is the
characteristic color such as that smelted at Neusohl in the Carpathian
mountains of Hungary; from Cotteberg, Bohemia; from Norway; and from
the Harz forest. Some is a dark red as that from the Gairum and
Schneeberg mines, Misena. Some from Gairum is whiter and we are wont to
call it white copper even when it is also dark red. Pliny mentions
white copper but does not say if it was smelted from a vein or tinted
with lodestone. A yellowish red copper is produced in smelters that
separate silver from copper and this is called yellow or regulare copper. In the same smelters a dark yellowish-red copper is produced which is known as caldar-ium copper. The German name for this13 is derived from lebes, a bronze cauldron. I shall say more about each of these later. Regulare differs from caldarium copper
in that the former is easier to forge than cast, the latter easier to
cast than forge, in fact it breaks under the hammer. Copper containing
zinc has a golden color and is called opeixakKos. Pliny writes
that this is also found in mines and for a long time was regarded as
especially beautiful and desirable. Lodestone gives it a white color.
Chemists can change the color to silver or gold so that it resembles
varieties of these metals. It glows in a fire, melts and can be cast.
Copper is not affected by fire when placed in a large shallow vessel,
yet when placed in the same vessel with the materials that purify gold
and silver it is entirely consumed. It is hard but can be hammered into
thin sheets. Pliny writes that when copper is beaten into sheets and
tinted with the gall of a bull it resembles gold and since it is used
in crowns that are worn by actors it is called coronarium copper.
When one-sixth ounce of gold is added to an ounce of this copper a thin
sheet burns with a flame the clear red color of pyrope garnet. Copper
objects such as nails are shattered by the force of cold. Eratosthenes
tells of a copper jug which a priest named Stratius placed in the
temple of Aesculapius near Panticapaeum and was broken by the
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13 Lebetezkupfer.
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