Crystallized Quartz Enlarge
Dec. 1. 1807. Publish’d by Ja.s Sowerby. London.
British Mineralogy
CCXLI
Silex Quartzum

Crystallized Quartz

  • Class 2. Earths.
  • Order 1. Homogeneous.
  • Gen. Silex.
  • Spec. 1. Quartz.
  • Div. Crystallized.

This curious specimen was collected long since by our late worthy friend Mr. W. Day, in Derbyshire; and as we have not seen the like elsewhere, we consider it as a valuable specimen. It is not uncommon to sec Quartz on Galæna; but when it occurs in eighteen-sided crystals fairly terminated at both ends, the prism elongated, and mostly perpendicular upon all the faces of the Galæna, whether the Galæna be cubical or octaëdral, it is very remarkable. Indeed the Quartz in general appearance resembles small seed or grains, which, when perfectly well crystallized, are not common. They are sometimes dispersed, though adhering in bundles to each other, as figured at the bottom of the plate, and occasionally terminated by three-sided summits.

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