rhombohedral's Usage Examples:

The Helena crystals are of tabular habit, being composed of the basal pinacoid with a very short hexagonal prism, whilst at Yogo Gulch many of the crystals affect a rhombohedral habit.

They all crystallize in the monoclinic system, often, however, in forms closely resembling those of the rhombohedral or orthorhombic systems.

Hot or dilute cold solutions deposit minute orthorhombic crystals of aragonite, cold saturated or moderately strong solutions, hexagonal (rhombohedral) crystals of calcite.

6° the mass becomes doubly refracting, and from a solution rhombohedral (optically uniaxial) crystals are deposited; by further cooling acicular rhombic crystals are produced at 82.

"Siderite, or spathic iron ore, FeCO 3, crystallizes in the rhombohedral system and contains 48.

Siderite, or spathic iron ore, FeCO 3, crystallizes in the rhombohedral system and contains 48.

Although bismuth is readily obtained in fine crystals by artificial means, yet natural crystals are rare and usually indistinct: they belong to the rhombohedral system and a cube-like rhombohedron with interfacial angles of 92° 20' is the predominating form.

Quartz crystallizes in the trapezohedral-hemihedral class of the rhombohedral division of the hexagonal system.

It is readily soluble in water, and on evaporation in a vacuum over caustic lime it deposits colourless, rhombohedral crystals of 2KHS.

Although bismuth is readily obtained in fine crystals by artificial means, yet natural crystals are rare and usually indistinct: they belong to the rhombohedral system and a cube-like rhombohedron with interfacial angles of 92° 20' is the predominating form.

Distinct crystals are rarely met with; these are rhombohedral and isomorphous with arsenic and bismuth; they have a perfect cleavage parallel to the basal plane, c (111), and are sometimes twinned on a rhombohedral plane, e (1 ro).

GRAPHITE, a mineral species consisting of the element carbon crystallized in the rhombohedral system.

There are perfect cleavages parallel to the rhombohedral faces, and the crystals exhibit a strong negative double refraction, like calcite.

Synonyms:

symmetric, symmetrical, trigonal,

Antonyms:

asymmetrical, oblique, irregular, perpendicular,