Wulfenite is a lead molybdate mineral. It can be most often found as thin flat like crystals with a bright orange-red to yellow-orange colour, sometimes brown, although the colour can be highly variable. In its yellow form it is sometimes called "yellow lead ore". Wulfenite was first described in 1845 in Austria and it was named for Franz Xavier von Wulfen (1728-1805) who was an Austrian mineralogist.