Dog's Tooth Calcite | Rebel Angel Crystals
Calcite fluoresces pink under long wave ultraviolet light, and blue under short wave. In spite of its range of colour and habit, it is easily recognised by its softness, strong perfect cleavage, and reactivity with even mild acids - a drop of vinegar will create a 'fizz', dissolving the calcite it touches (this is an easy way to identify limestone as well). Coloured calcites from Mexico ...