I DATOLITE. 257 XXV. BORACITE FAMILY. This Family contains the following species, viz. Da- tolite, Botryolite, and Boracite. 1. Datolite. Datholit, IVerner. Chaux Datliolitc, Brong. t. ii. p. 3.9"- Id Haut. s. 123. Id. Karsl. Tube I. s. 17—Chaux boratee silirieuse H any', Tabl. p. 17. Datolit, Lcnz, b ii. s. 859- Id Allan, p. 127. External Churactem. Its colours are greyish-white, milk-white, greenish- 'v Lite, greenish-grev, which latter inclines to celandine- green, and rarely lo muddy honey yellow. It occurs massive; and crystallised in the following figures. 1. Oblique four-sided prism ', which is very rarely per fect, generally truncated on the angles and lateral edges; sometimes also bevelled on the lateral edges. When the truncations on tin angles becomes so large that they meet, there is formed 2. An oblique four-sided prism, flatly acuminated with four planes, which are set on tlje later .i erges. The crystals are small, seldom middle-sized, aim form druses: thev are sometimes rough, sometimes smooth, “nd splendent. Vol. II. it Internally ■ According to llmnnmnn. the pr.mii o figure is an oblique four-sidcd Pri,rn > having lateral edges of 7t° dlT and 103° 30.