FluoroSpec reagent is methylammonium bromide dissolved in isopropanol. When it touches lead-bearing pigment, the lead ions and the MABr form a perovskite quantum dot at the surface. Under 365nm UV, the quantum dot fluoresces bright green. No lead, no quantum dot, no glow.
MABr is a salt. Isopropanol is the carrier. When a drop lands on a lead-bearing surface, the lead ions combine with the MABr to form CH3NH3PbBr3, a hybrid organic-inorganic perovskite. The perovskite is a quantum dot. Quantum dots fluoresce at a wavelength set by their composition. CH3NH3PbBr3 fluoresces green (525nm) under 365nm UV.
Perovskite quantum dots have a photoluminescence quantum yield above 80%. Laboratory-grade brightness. The naked eye sees it instantly under handheld UV.
Plain ceramic is fired clay. There is no lead in the matrix. The decoration was painted on top and fired into the glaze. The reagent reaches the decoration through the glaze porosity and reacts with whatever lead-bearing pigment was used. The clay stays inert.
Drip for dishes. Spray for walls, dust, soil.
The isopropanol flashes off. The MABr stays in contact.
Hold the UV lamp 6-12 inches from the surface.
