Adamite, Ojuela Mine, Mapimí, Durango, Mexico
This is an interesting specimen of adamite from the Ojuela Mine, Mapimí, Durango, Mexico. As is the case with many fluorescent minerals, there tends to be tremendous variability in the brightness of the fluorescent response among various adamite specimens, even those from the same location. Some fluoresce only dimly under short wave and show little to no response under long wave, while others fluoresce brightly under both wavelengths. This particular specimen is one of the brightest that I've seen, and responds nicely under both UV wavelengths. In addition, the bright green fluorescent adamite crystals sit on a bed of smaller white crystals of a second, unidentified mineral (perhaps calcite or aragonite) that fluoresce blue to blue/white, and provide a beautiful color contrast to the brightly fluorescent adamite. The unidentified mineral is also phosphorescent. The size of this specimen is 65 x 45.x 28 mm, and it weighs 72 grams.
The photographs above show the short wave UV fluorescent and phosphorescent response. The well developed adamite crystals fluoresce bright green and the smaller unknown mineral crystals show a blue response. The unknown mineral displays blue phosphorescence after the short wave source is turned off. Mouse over scrolling images for photo information.
As seen in the above photographs, the specimen shows a similar, but less bright fluorescent response under long wave UV. The phosphorescence of the unknown mineral crystals is also dimmer following long wave, but interestingly has undergone a color shift to pale green.
Visible light photograph, above, of the same specimen showing the yellow colored adamite crystals perched on a bed of the unknown white mineral, all on top of a contrasting matrix of red/brown limonitic gossan.