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134
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DE NATURA FOSSILIUM
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Albertus
among the Sequani between Basilea and Strasbourg. It is found in
Greater Germany in many places, for example, in a deserted mine of
Mittelbach five miles from Chemnitz, Misena; in a second mine five
miles from the first near the town of Langovicius; in a valley between
the town of Zuicca and a mountain containing coal. In the latter place
it occurs in veins of pure onyx as well as in a black breccia. It is
found in Cappadocia near Galatia; in many parts of Scythia; and
according to Pliny especially in Carmania, Arabia and India. The onyx
found among the Germans and Sequanians as well as other stones similar
to it is called chalcedonius (chalcedony). The name is derived
from Chalcedon, Bithynia, a town to which this mineral was brought from
either Cappadocia or from some other nearby place. All the rest is
known by the old name onyx although Pliny calls the mineral from
Carmania both onyx and murrhina.n
The
color of onyx varies greatly. It may have veins that are fiery red, red
and purple with layers that are milk-white such as the German material.
It may be fiery red, black, horn-yellow with white circles which
resemble the white portion of the eye, according to Pliny, such as the
stones from India. The Arabian stones are black with white layers. The
stones from Scythia and Carmania have fire-red, purple and milk-white
layers. As I have said, Pliny calls these latter stones murrhina. Certain
gray stones are found with whitish zones that give them the appearance
of an eye. Some have blue layers while the German stones rarely have
black, often bluish black and, besides the colors already mentioned,
blue and blackish red. The veins or bands found in these stones may be
broad or narrow. They may curve smoothly or crookedly and even form
eddies which resemble waves. Some of these stones reflect colors such
as those seen in the rainbow, according to Pliny. In the shrine of The
Three Wise Men, or as we call them, The Three Kings, at Cologne there
is a piece of onyx three inches wide with milk-white bands that run in
all directions in such a manner that they portray the heads of two
youths with a black band resembling a serpent running from the forehead
of one to that of the other and the head of an Ethiopian with a black
beard. The beard is on top of the jaw bone of one of the white heads.
The rest of the gem has the same color as a fingernail. Albertus has
also described this same gem. The layers of onyx, no matter what their
color, are usually translucent except the black and milky white layers
which are opaque. Very often coats of arms are engraved on pieces of
white German onyx and these are highly prized by the nobility since
they are more transparent than any other onyx and harder than quartz
although less transparent. In addition, these stones are backed with
colors that tint the coat of arms with the proper colors. The German
stones are sometimes used for the little spheres with which we
calculate prices as well as for the hilts of swords, goblets and the
small mortars in which they grind emery. They
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Chalcedony is a variety of cryptocrystalline quartz and onyx a variety
of chalcedony with straight parallel banding. Some of the "onyx"
mentioned here is banded calcite, the Egyptian alabaster of the
ancients.
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