Thursday, July 5, 2012

Gemstone of the Week: Wulfenite

(Image of Wulfenite sample found at Cochise College)

Wulfenite is a minor source of the mineral molybdenum.  It generally forms as thin, square plates or as beveled tabular crystals.  However, granular or massive forms are also known to occur. Wulfenite may be red, orange, yellow, brown, or gray in colour.  It was discovered in 1845 by Frantz Xaver von Wulfen after whom it is named.  Some of the best samples of Wulfenite may be found in Solvenia, Mexico, China, Zambia, and the state of Arizona.  This gem forms as a secondary mineral in the oxidized zone of lead and molybdenum deposits and often occurs along with Cerussite, Vanadinite, and Pyromorphite.