Tyuyamunite: Margaritas No. 1 Mine, Sierra Peña Blanca, Peña Blanca District, Mun. de Aldama, Chihuahua, Mexico
This is a calcium uranyl vanadate. The vanadate ion has some proper fluorescence of it's own, so it overlaps with the familiar uranyl fingerprint. This makes it difficult to say anything sensible when looking at the emission spectrum. Interested parties may freely download the spectral data from my website: both in cm-1 and in µW/cm²/nm or absolute spectral irradiation. The fluorescence was photographed in 405 nm laser light. The white light photo was taken in halogen light.
It's not a very desirable specimen but it is representative for the species.
