Description: 1 - Halogen 2 - UVA (385 nm, filtered) 3 - UVC (255 nm, filtered) Big piece at left has a mild blue-green-whitish fluorescence both under LW / SW Second piece is Sulphur and calcite, which looks green-whitish both under LW / SW Big rhombohedron is inert both under LW / SW Piece on the right is a semi-dissolved calcite rounded by feldspar. This calcite is almost inert with LW but glows in dark red under SW Cluster on base at left emits in red both under LW / SW Second cluster at center is almost inert in LW and looks somewhat red under SW The two generations of calcite in speleothem have a strong differentiated fluorescence. In this case activators are organic compounds. Cobaltoan calcite is nearly dead under LW and revives strong with SW Small rhombohedron at left looks dull red in LW and turns to orange with SW Tabular crystal increases his red brightness from LW to SW Small dogtooth calcite at front is the brightest piece, whitish red under LW and pure white with SW Small rhombohedron at right that looks red both under LW / SW is accompanied by something blue, at last! what a surprise! After closer inspection turns to be fluorite. This piece has also galena, so is probable Pb is acting as coactivator under SW, emiting LW which amplifies other activator responsible of red fluorescence.

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