DIAMOND

DIAMOND A beautiful limpid diamond crystal, with 4.60 carats from Rio Velho, Minas Gerais, on display at the Museu Amsterdam Sauer, in Rio de Janeiro. Photograph taken by Marcelo Lerner. The diamond has a cubic crystalline structure, and its most common habit is the octahedron. Its high refractive index confers intense shine and make it the most appreciated gemstone when lapidated.