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BOOK V
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91
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in the same manner but has less admixed water. While man, through his ingenuity, makes gypsum from lapis specularis, nature on the other hand sometimes makes lapis specularis from gypsum. Its name comes from speculum because it is transparent and, having been polished, will reflect the image of anything on one side. It is called σβληνίτης by
certain Greeks either because it was usually found at night when the
moon was increasing in size or because it drew within itself the image
of the moon at night or because it was pellucid and reflected the exact
image of the moon each day showing the increase and decrease in size.
Others called it αφροσίληνος because many had become convinced
that the moon was made of this mineral just as the ignorant have become
convinced of the even greater absurdity that it is foam of the moon.
According to Aetius Amidenus it is called διαφανής because it is transparent and for the same reason σφβκλάρίος from a corruption of the Latin name. Certain Germans have given it the name glacies or ice because of the marked resemblance of the two materials.
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Bermannus. "You are referring to native gypsum?
Naevius.
"Of course. Pliny copies Theophrastus and writes, "And it is dug from
the earth, as in Cyprus, at the surface. For Theophrastus says that the
miners remove little earth."
Bermannus. "That is the way it is found. Lapis specularis from which gypsum is made is thus described by Pliny, "The best of all is known to be made from lapis specularis or material having such scales."
Naevius. "You have mentioned these under things that are found here and which can be used in medicine and in our buildings.
Bermannus.
"They are found in several places and along the Elbe river for when it
overflows it sometimes carries these minerals. Gypsum is sold by the
common people and we use their name. They call lapis specularis 'Mary's
Ice,' concerning which Pliny has written most exhaustively, it seems to
me. Selenite is well named since it splits with exceptional ease into
very thin sheets. At one time Spain produced a large amount of this
mineral from an area within one hundred miles of the town of Segovia.
Today it is produced in Cyprus, Cappadocia, Sicily and especially
Africa. The softest and largest pieces from Spain and Cappadocia are
the most valuable although they are dark. There are, in a part of
Bononia, Italy, small spotted pieces bound together with the
surrounding hard stone that have an appearance very similar to the
material which is dug from the deepest parts of the mines in Spain.
Also it is found included in rock within the earth and is mined. To
date pieces which occur free in nature have not been found that are
longer than five feet. Certain ones say that, just as a humor of the
earth is frozen into quartz and congealed into a stone, the marrow of
the bones of wild animals that fall into certain pits is changed into
this mineral by nature after a winter. Occasionally it is found black
but it is usually an intense white, when it is quite soft, from the
effects of sun and weather. It will not deteriorate, if it is not
injured, when it is taken from rocks of many genera. They have found a
use for the fine material for sprinkling around the outer part of the
circus during the games in order to give it a dazzling white color.
Pliny writes this about selenite and nothing could be more clear.
Naevius. "He expresses our opinion when he says that it is frozen like quartz and for that reason is called 'Mary's Ice' (Marieneis).
Bermannus. "That is right. A blackish variety is found in this vicinity which is not
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