powellite

== English == === Etymology === Named after American geologist John Wesley Powell (1834–1902), +‎ -ite. === Noun === powellite (countable and uncountable, plural powellites) (mineralogy) A tetragonal-dipyramidal mineral containing calcium, molybdenum, and oxygen. === Further reading === David Barthelmy (1997–2026), “Powellite”, in Webmineral Mineralogy Database. “powellite”, in Mindat.org, Keswick, Va.: Hudson Institute of Mineralogy, 2000–2026.