Schalenblende (wurtzite + sphalerite), Pomorzani Pb-Zn mine, Olkusz, Poland.
17 * 12 * 1.5 cm.
Activator: uncertain, possibly a mix of manganese , copper, silver, and crystal defects.
Short wave UV
Sphalerite (orange), aragonite (white) and calcite (red): Passa Limani Cove slag locality, Passa Limani area, Lavrion District, Attikí Prefecture, Greece.
Click the prism to see the spectrum of the sphalerite orange fluorescence explaned.
Long wave UV
Schalenblende (wurtzite + sphalerite)
Sphalerite, aragonite and calcite
Sphalerite var. marmatite
Dongxian District, Fezhou city, Jiangxi, China.
Marmatite is an iron containing variety, (Zn, Fe)S, of sphalerite characterized by a dark grey to black color.
You shouldn’t look for fluorescence with black minerals. Because they are black, they by definition absorb all the light that falls on them, including UV, as well as any light they would generate from fluorescence. This specimen appears to be an exception but it is not.
Somewhere during the final phase of the growth of these crystals, the source of the iron has become depleted and an extremely thin layer of ordinary sphalerite has deposited on the black marmatite (marmatite is not a recognized mineral but only a variety of sphalerite). The orange fluorescence is created in that layer.
Sphalerite fluoresces frequently and for many reasons. Crystal errors and a multitude of activators such as manganese, silver, copper and chlorine, aluminum, indium, gallium and thallium, usually in combinations with each other or with errors in the crystal lattice where zinc atoms are missing. The specimen in the photo is a very simple case where only divalent manganese replaces zinc.
This specimen is 7 cm wide and also highly tribomuminescent.
