Calcite, France

Very sharp calcite needles that fluoresce a stong greenish white with an equally strong phosphorescence. Clearly some polycyclic aromatic hydrocarbons are present. Probably in the form of humic acids. Photo under SW-UV and white light.

Cap Blanc-Nez (Escalles), Pas-de-Calais, Nord-Pas-de-Calais, France.