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GEMS.
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the
agate jasper and the onyx jasper. It is found in round, opaque pieces,
and has a concave breakage ; the opaque parts are pure jasper, and the
zones or circles, agate. It is slightly translucent near the edges ;
hard and easily broken. Besides Egypt, it is found in the Grand Duchy
of Baden, in a bed of ferruginous red clay. The brown kind has the
different tints of its colours arranged in concentric layers ; it is
found particularly in the sands of Egypt, near the Pyramids, in round
pebbles ; it has little brilliancy, and its breakage is concave.
Sometimes Egyptian jasper is called jasper of Ethiopia.
3.
Striped Jasper.—This is of grey, green, red, and yellow, disposed in
stripes which form designs in flames or spots. All jaspers belonging to
this division, which contain more than three colours, are called
flowered or variegated. Those that have a white stripe on a red ground
are known as " grammasio." Striped jasper is found in a secondary
argillaceous porphyry, in Scotland, Siberia, Corsiia, and in Sicily,
where it is very common.
4. Universal Jasper.—Présents a very great variety, without any distinct design.
5.
Porcelain Jasper.—Is an imperfect volcanic vitrification, of a grey,
blue, or yellow colour. It has natural crevices in every side ; is
opaque, not bright, and much softer than other jaspers. It can be
melted, and becomes in that case a white or grey glass. It is found
near vulcanized earths, and in every place where mud has been in
combustion. Germany and England fur-
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