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Wulfenite is a lead molybdate mineral with the formula PbMoO4. It can be most often found as thin tabular crystals with a bright orange-red to yellow-orange color, sometimes brown, although the color can be highly variable. In its yellow form it is sometimes called "yellow lead ore". It crystallizes in the tetragonal system, often occurring as stubby, pyramidal or tabular crystals. It also occurs as earthy, granular masses. It is found in many localities, associated with lead ores as a secondary mineral associated with the oxidized zone of lead deposits. It is also a secondary ore of molybdenum, and is sought by collectors. ==Discovery and occurrence== Wulfenite was first described in 1845 for an occurrence in Bad Bleiberg, Carinthia, Austria.〔 It was named for Franz Xavier von Wulfen (1728–1805), an Austrian mineralogist.〔 It occurs as a secondary mineral in oxidized hydrothermal lead deposits. It occurs with cerussite, anglesite, smithsonite, hemimorphite, vanadinite, pyromorphite, mimetite, descloizite, plattnerite and various iron and manganese oxides.〔 A noted locality for wulfenite is the Red Cloud Mine in Arizona. Crystals are deep red in color and usually very well-formed. The Los Lamentos locality in Mexico produced very thick tabular orange crystals. Another locality is Mount Peca in Slovenia. The crystals are yellow, often with well-developed pyramids and bipyramids. In 1997, the crystal was depicted on a stamp by the Post of Slovenia. Lesser known localities of wulfenite include: Sherman Tunnel, St. Peter’s Dome, Tincup-Tomichi-Moncarch mining districts, Pride of America mine and Bandora mine in Colorado. Small crystals also occur in Bulwell and Kirkby in Ashfield, England. These crystals occur in a galena-wulfenite-uraniferous asphaltite horizon in a magnesian limestone. The wulfenite found in this area is similar in properties (paragenetic sequence, low silver and antimony contents of the galenas and absence of pyromorphite) to the wulfenites of the Alps and may be similar in origin. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wulfenite」の詳細全文を読む スポンサード リンク
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