Common Asbestus Enlarge
July 1. 1807. Publish’d by Ja.s Sowerby London.
British Mineralogy
Silex magnesiatus

Common Asbestus

  • Div. 2. Imitative.
  • Var. Fibrous.

This substance has been long known in the Isle of Skye. I believe it has not been discovered in Ireland, but may perhaps be found in North Wales. The length of the fibres in the present specimen gives it a remarkable appearance, and the leek-green varieties but faintly convey the idea of a stone, particularly in a figure. It is scarcely flexible, except in very small fragments, al though it has that appearance, especially the middle twisted piece. It is finely fibrous in its divisions in some parts, in others rather solid and plated. Fragments splintery, breaking with hanging fibres. Lustre rather internal, partly pearly. To the touch it is smooth and softish, scarcely greasy; is readily scraped with a knife, and is somewhat transparent at the edges. The lighter left hand specimen is more solid, and mixed with the amianthine rock, in a curious semi-detached manner; breaking at right angles, The varieties between these may include most known, as there are but small differences. It sometimes approaches Lapis nephriticus, which is more solid, tough, and hard.—Spec. Grav. from 2.547 to 2.995.

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