1) Oxide mineral
Found on
https://www.crosswordclues.com/clue/powellite
Powellite is a calcium molybdate mineral with formula CaMoO4. Powellite crystallizes with tetragonal - dipyramidal crystal structure as transparent adamantine blue, greenish brown, yellow to grey typically anhedral forms. It exhibits distinct cleavage and has a brittle to conchoidal fracture. It has a Mohs hardness of 3.5 to 4 and a specific gravi...
Found on
http://en.wikipedia.org/wiki/Powellite
(from the article `molybdate and tungstate minerals`) Among the molybdate and tungstate minerals, only the powellite-scheelite series (calcium-bearing molybdate/tungstates) and wulfenite (lead molybdate) ... ...specific gravity, 5.9–6.1; and crystal system, tetragonal. Scheelite is one end-member of a continuous series of solid sol...
Found on
http://www.britannica.com/eb/a-z/p/103
No exact match found.
