octahedron Definition

cubo, dodecahedron, polyhedron, tetrahedron, icosahedral, spinel, corundum, smoky quartz, feldspars, cabochon, alexandrite, pyrope, chalcedony, sepal, punctate, lamellae, aventurine, phlogopite, boron nitride, beryl, azurite, plagioclase, crystallites, morganite, ellipsoids, labradorite, laths, carnelian, phyllite, midrib, eclogite, aluminosilicate, chrysocolla, uraninite, zirconium oxide, peridot, argentiferous, greisen, nephrite, pontil, hornblende, muscovite, marcasite, lapilli, chromophore, electrum, covellite, carbides, birefringence, cadmium sulfide, quasicrystal, drupe, pyrochlore, allanite, siderite, micrograph, micrometre, carnotite, condyle, nacre, eosin, chalcocite, striations, mylonite, papule, dentine, diffraction grating, conic, martensite, cementite, verdigris, blebs, agarose, fibril, goethite, cherty, autunite, calyx, albite, scheelite, amphibolite, pentlandite, calculi, tetrahedrite, laminae, openwork, synclinal, trabeculae, tesserae, jadeite, realgar, claystone, citrine, lunate, umbels, threadlike, mgo, diopside, spicule, yttrium oxide,