Mineral Type - Wulfenite
Wulfenite is fairly rare but is known from Namibia and Congo. The mineral was named after the Austrian mineralogist, Frantz Xaver von Wulfen (1728-1805). Wulfenite is a secondary lead mineral which ranges from yellow to orange in colour. Wulfenite is recognised as being fluorescent and under short to long UV is generally yellow to orange to red. A very rare and very beautiful mineral species for the collectors.
Question: Are the yellow crystals with the dioptase from Congo not Mimetite? Answer: Definitely Wulfenite. Vanadium comes from this deposit. Mimetite in SA only comes from Wessels Manganese mines and has 6 sided flat topped beryl like crystals and is not recorded from Brazaville/Congo. We also have orange Vanadium Wulfenite from Kaokoveld dioptase/Shattuckite deposit, so they are often associated but rare...especially good crystalline specimens. It is definietly a classic Museum piece and is rare and very spectacular...it would have been an absolute cracker Dioptase without the bright yellow Wulfenite, but with it....hmm yummy!! The photos dont come close to doing that specimen even 50% justice with the intensity of the emerald green real colour...as you you know, we battle (unless we get filters) to capture the emerald greens. By NJ May