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214
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DE NATURA FOSSILIUM
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Cadmia is black, yellow brown, or gray. Like the cadmia produced
in furnaces this mineral occurs in various forms. Some has the
appearance of grapes, some occurs in cubes while some forms in crusts.
Natural cadmia is more potent than that formed in furnaces.
Actually it is so corrosive that it will eat the moist hands and feet
of a miner. It differs from pyrite both in color and other properties.
Pyrite, unless it contains sulphates, is either a golden or silver
color, rarely any other, while cadmia is black, yellow brown,
or gray. The former will cure gatherings while the latter is a deadly
poison and will destroy any living substance. It is used to kill
grasshoppers, mice and flies.26
This cadmia, like quicksilver, is placed in a flask and heated until the
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tities
are found at Rauris. The latter mineral contains more silver than gold
while the former contains only gold or very little silver mixed with
the gold. Another species is also gray and is found in quite small
grains at Reichenstein. It is mixed with the last species and gold is
obtained from it. It is also found at Aldenberg, Silesia, where it has
a somewhat different character and both gold and silver are obtained
from it. Our miners also call this species kisum. (Note, kisum is probably arsenopyrite, a sulph-arsenide of iron.)
Naevius. "When we come upon it will you show it to us?
Bermannus.
"Certainly. But returning to the pyrite with both a silver and golden
color, it is often found in silver mines and more commonly in separate
veins that are completely sterile, as I have already mentioned.
Naevius. "What use does it have in metallurgy?
Bermannus.
"When it is found in large quantities it is melted into a kind of stone
that is widely used in silver smelting. This pyrite is common in rivers
and many chemists have collected it, only to be laughed at since it is
almost sterile.
Naevius.
"Aside from these species Pliny mentions another saying people have
another species of pyrite that is very heavy and has a large amount of
fire." 25 This may refer to the cobalt arsenides smaltite, cobaltite and their oxidation
products. That it includes cobalt minerals is evident from the following excerpt
from Bermannus, page 467,
Bermannus. "This genus the miners call cobaltum, a name I believe we can now use, the Greeks call cadmia. The
essences from which pyrite and silver are formed are seen to have
congealed into a single body and thus has been created that which the
miners call cobaltum (cobalt). There are those who believe it
to be the same as pyrite since they have almost the same composition
and there are others who regard it as a separate genus as do I. Very
often it possesses an extraordinary corrosive quality so that it will
eat into the hands and feet of workmen unless they take careful
precautions against it. We know that pyrite will not do this. There are
three species of this mineral which are more easily distinguished by
color than by any other property. These are black, gray, and
iron-colored. No matter what else they may contain there is usually
more silver than in pyrite." It is possible that the black mineral is
asbolan or heterogenite impure mixtures
of cobalt and other metals that are found in Hesse, Thuringia, and other German
localities. The gray and iron-colored minerals probably refer to several cobalt
minerals but particularly to smaltite which has the same crystal form as pyrite
and is associated with silver in some German mines.
The
derivation of cobalt through kobold, kobelt, etc., is interesting. The
alchemists and miners of Saxony derived the name from the Greek root
word καβάλος
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