The mineral in question was put into the author's hands by Mr Rose, mineral-dealer of this city, as a substance supposed to be a variety of mesotype. Mr Rose obtained it from Count Vargas Bedemar of Copenhagen, who had brought it from Faroe.

It has a pure white colour, with some opalescence and translucence, a glistening vitreous lustre, and somewhat greater hardness than fluor. Its texture is imperfectly fibrous; but the fibres in some places diverge with considerable regularity, shewing an approach to a crystalline structure. The specific gravity is 2.362; it is remarkably tough and difficultly frangible, so as to require much time and labour to separate a mass of it into smaller fragments.