scalenohedral

The crystals measure up to a yard across, and are rhombohedral or scalenohedral in habit; their faces are usually dull and corroded or coated with stilbite.

Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" Various

Crystals of calcite are extremely varied in form, but, as a rule, they may be referred to four distinct habits, namely: rhombohedral, prismatic, scalenohedral and tabular.

Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" Various

Fine crystals of prismatic habit twinned according to this law were formerly found in considerable numbers at Wheal Wrey in Cornwall, and of scalenohedral habit at Eyam in Derbyshire and Cleator Moor in Cumberland; those from the last two localities are known as "butterfly twins" or "heart-shaped twins" (fig. 10), according to their shape. iv.

Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" Various

Depending on the habits of the crystals, certain trivial names have been used, such, for example, as dog-tooth-spar for the crystals of scalenohedral habit, so common in the Derbyshire lead mines and limestone caverns; nail-head-spar for crystals terminated by the obtuse rhombohedron

Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" Various

The epitome of South African rhodochrosite is represented by gemmy, deep red scalenohedral crystals in solid clusters such as the beautiful 9. 5-cm example pictured here.

Museum Blogs 2009

The epitome of South African rhodochrosite is represented by gemmy, deep red scalenohedral crystals in solid clusters such as the beautiful 9. 5-cm example pictured here.

Museum Blogs 2009

The epitome of South African rhodochrosite is represented by gemmy, deep red scalenohedral crystals in solid clusters such as the beautiful 9. 5-cm example pictured here.

Museum Blogs 2009