Silver chloride is a chemical compound with the chemical formula Ag . This white crystalline solid is well known for its low solubility in water (this behavior being reminiscent of the chlorides of Tl+ and Pb2+). Upon illumination or heating, silver chloride converts to silver (and chlorine), which is signaled by greyish or purplish coloration to some samples. AgCl occurs naturally as a mineral chlorargyrite.