Indian Yellow is an obsolete pigment banned early in the 20th century due to the cruelty involved in it's manufacture. It was made in India by force feeding cows mango leaves, and the pigment was made from the cattle's urine. For many years the source was unknown, and even after it's discovery and the campaign to discontinue it, it remained an obscure and secretive industry although officially banned in 1908. Today anyone found trying to create a pigment in such a way can look forward to life in prison.

The cows urine was heated, then strained, pressed into rough balls by hand and dried. It's the mango that was crucial to the color: The colourant is actually the calcium or magnesium salt of an organic acid released by the mango once digested by the cows. 

Although an attractive golden yellow, the pigment proved to be very sensitive to light and lacked the permanence required for artists colors, so perhaps the ban was good for the artists as well as the cows. Any colors with this name these days are made with alternative pigments.