Indian yellow is a complex pigment mainly composed of salts of louisantic acid (magnesium louisantate and calcium louisantate), euxanthine and euxanthine sulphonate. Also known as Purree, Snowshoe Yellow, Gaugoli, Gogili, Hardwari Peori, Monghyr Puri, Peoli, Peori, Peri Rung, Pioury, Piuri, Purrea Arabica, Pwree, Jaune India (French, Dutch), Indian Yellow (German), Yìndù huáng (Chinese), Indian yellow (Italian), Indian yellow (Spanish). The crystalline form was dissolved in water or mixed with oil to produce a transparent yellow paint used in Indian frescoes, oil paintings and watercolors. Upon application, Indian Yellow produces a clear, intense and brilliant yellow-orange color that appears particularly vivid and brilliant due to its fluorescence in sunlight. It must have an unpleasant smell. It was most commonly used in India during the Mughal period and in Europe in the 19th century before becoming commercially unavailable around 1921. The origin and production of Indian yellow has long been a matter of debate, in part due to the discrepancies between the sources themselves, which contain both pure materials and mixtures of chromium salts, dyes of vegetable and animal origin. Studies in 2018 on a sample collected by TN Mukharji in 1883 confirm his observations that it was obtained from the concentrated urine of cows fed mango leaves.