This paper discusses the five distinct native gold crystal morphologies that were identified in samples collected from the Amanuma mine, Gunma Prefecture, Japan. These include: 1) Single crystals of octahedrons composed of o{111} faces, and tetradecahedron in which the a{100} faces truncate the apex of the o{111} octahedron; 2) octahedral crystals elongated along one of <110> directions; 3) triangular pyramids with d{110} sloped faces formed on an o{111} surface, and frustum of the triangular pyramids; 4) crystals elongated along the c-axis of pseudo-trigonal system; and 5) parallel intergrowths in which octahedral crystals overlap in the direction of the elongation of a crystal. These various morphologies are hypothesized to be the foundation for the growth of feathery (vein-like) aggregates, which then undergo contact twinning to finally produce a dendritic morphology in some native gold specimens.

Three types of “Star of David” have been found from spinel crystals collected in Mogok, Myanmar：（1）Two triangular flat crystals contact with 60° rotation,（2）A hexagonal flat plate is inserted between the two triangular flat crystals and（3）A spinel twin is partially covered with a triangular flat crystal. Shapes of the “Star of David” crystals are readily understood when they are drawn in pseudo-trigonal system. The “Star of David” crystals are quite rare, and are found in Mogok. Therefore, I propose to call the crystals Mogok spinel-type twin.

This paper reports the first finding procedure of gem-quality V-bearing green grossular (tsavorite) and related more V-rich garnet (goldmanite) from the Sør Rondane Mountains, East Antarctica. These garnets are divided into three types; type-1 garnet is a large porphyroblast with gem quality tsavorite affinity, type-2 garnet shows symplectite composed with An-rich plagioclase and quartz at kelyphite rim surrounding type-1 garnet, and type-3 garnet is the most V-rich fine-grained porphyroblast found in the matrix. The garnets formed during the granulite-facies metamorphism of Pan-African era (ca. 620 Ma) in the continental collision zone of East- and West- Gondwana continents, namely the East African – Antarctic Orogen (EAAO), as well as the V-bearing garnets from Kenya, Tanzania, Madagascar, and Sri Lanka.