strong very weak 33 Descloizite Sahlinite Columbite-(Fe) few, redbrown fine red yes specs Loveringite...Ilmenorutile Powellite Davidite(Ce, La, Y) Tapiolite-(Mn) Sphalerite Wurtzite Groutite Wolframite Thorianite...Madenköy Mine, Çayeli, Rize Province, Black Sea Region, Turkey (sample: Halbach); XPL If marked in description...Taymyrskiy Autonomous Okrug, Eastern-Siberian Region, Russia (sample: Melcher/Oberthür); PPL D Fine-grained...grey); Himmelsfürst Mine, Brand-Erbisdorf, Freiberg District, Erzgebirge, Sachsen, Germany (sample: Seifert); |