Page:A treatise on diamonds and precious stones including their history Natural and commercial.djvu/181

 ON THE DISTINCTIVE CHARACTERS OF THE SPINELLE RUBY.

THE Spinelle Ruby differs from the Oriental in two very decided characters: its color and its crystalline form.

color of the Spinelle is, as we have already stated, a full carmine red, but it never presents that rich mellow tinge, which attends the oriental. The inferior specimens vary considerably in intensity of color, but do not exhibit the angular lines and opalesceut appearance, which are so generally observed in inferior oriental rubies.

Spinelle usually occurs in well defined crystals, and frequently presenting the primitive form, a regular octahedron; which is sometimes truncated on the edges and angles. The oriental, on the contrary, is very rarely found crystallized, but generally in rounded fragments.