"Optical" calcite - Gatineau area, Quebec, Canada
The specimen shown here, while not having the most spectacular brightness, is still a really nice display piece. Its transparency makes it look like a backlit gem when fluorescing under UV! It is at its best under midwave, followed by longwave. Shortwave is quite dim, therefore not worth being shown. The specimen is just bright enough to be worth being put in a midwave display.
The now depleted locality in which it was found produced large (up to about ten inches wide) rhombohedral crystals, which unfortunately were badly etched; this specimen comes from one of these large crystals, that was broken into smaller pieces to reveal the internal clarity of this material. Some of the best crystals were left intact, but this one had lots of surface bruising and scratches.
Size: 8,1 cm X 7,9 cm X 4,5 cm
Midwave UV fluorescence