Schaalstein Enlarge
[Undated]
Exotic Mineralogy
CXIV
Silex laminosus

Schaalstein

  • Syn.
    • Schaalstein. Werner.
    • Tafelspath. Karsten Tabl. s. 44.
    • Spath en tables. Haüy Tabl. 66.
    • Tabular spar. Aikin 183.

Schaalstein is well recognized by its foliated fraccure, with laminffi parallel to the laces of an apparently rectangular prism, and by falling to pieces after a slight effervescence in Nitric acid. Its analysis also places it at a distance from any other mineral that bears an external resemblance to it. Haüy speaks of fractures in the direction of the diagonals of the prism, parallel to the sides of which it most easily breaks (which, by the bye, he says is slightly rhomboidal) and of other oblique joints; but the cross fracture is so splintery, that it must be a difficult matter to ascertain them with precision. It is seldom translucent, and in general is full of minute cracks in every direction; it is soft enough to yield to the knife, but scratches glass. The spec. grav. is 2.86. It has been found in the island of Ceylon, accompanying the Cinnamon-stone (see tab. 83,) and at Dognatska in the Bannat, in foliated Limestone of a blueish colour along with granular Hornblende of a light green colour and brown Garnets; specimens from this latter place have been selected for figuring.

The following is Klaproth’s analysis:
Silex 50
Lime 45
Water 5
100
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