Rhom·bo·he·dral a. Geom. & Crystallog. Related to the rhombohedron; presenting the form of a rhombohedron, or a form derivable from a rhombohedron; relating to a system of forms including the rhombohedron and scalenohedron.
 Rhombohedral iron ore Min. See Hematite.
 Rhombohedral system Crystallog., a division of the hexagonal system embracing the rhombohedron, scalenohedron, etc.
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 Hem·a·tite n.  Min. An important ore of iron, the sesquioxide, so called because of the red color of the powder. It occurs in splendent rhombohedral crystals, and in massive and earthy forms; -- the last called red ocher. Called also specular iron, oligist iron, rhombohedral iron ore, and bloodstone. See Brown hematite, under Brown.
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