A pyramidal form under the rhombohedral system, inclosed by twelve faces, each a scalene triangle.

Six sided polyhedron, similar to a bipyramidal hexagon, but the adjoining area at the center is diagonal between every side as opposed to being level. Other modifications might be present. Minerals shape this way are scalenohedral.

(sca-le´-no-he´-dron) A closed crystal form whose faces are scalene triangles; the hexagonal scalenohedron has twelve faces, and the tetragonal scalenohedron has eight.