Raspberry garnet var grossular, also called Rosolite. The main crystal is about 10mm in size. Nice orange/red fluorescence under longwave UV light, best under 405nm blue laser (but you need a filter to block the blue light).
The fluorescence spectra from a 405nm blue laser shows a broad peak centered at about 610nm due to Mn2+ substituting Ca2+ (the spike at 536nm is from the blue laser).
Fluorescence under 405nm blue laser (with blue blocking filter).
Normal light.
Fluorescence spectrum.
