| orientation. Good examples are the triangular shapes of fluorite grains cleaved on the octahedron or the rhomb-shaped...crystal structure as in natural and deformed halite, fluorite, and calcite. 44 I. D. MUIR In anisotropic...Coarsely crystalline material. t Betafite from Madagascar has a mean hardness of 642. isotropic TABLE...naturally occurring halides, halite, sy]vine and fluorite, are transparent or show only weak absorptions...Area, California, U.S.A.; C, ulex.ite, Kramer District, California, U .S.A. ; D , nitre, Humboldt, Nevada |
