Indian yellow

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Indian yellow
Systematic name	Indian yellow
Chemical formula	CxHxNxOx
Molecular mass	xx.xx g/mol
Density	x.xxx g/cm3
Melting point	xx.x °C
Boiling point	xx.x °C
CAS number	[xx-xx-xx]
SMILES	xxxx
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Indian yellow, also called euxanthin or euxanthine, is a transparent yellow pigment used in oil painting. Chemically it is a magnesium euxanthate, a magnesium lake of euxanthic acid. It is a clear, deep and luminescent yellow pigment. Its color is deeper than gamboge but less pure than cadmium yellow.

Euxanthic acid itself is a glycoside, a conjugate of the aglycone euxanthone with a molecule of oxidized glucose derivative. ^[1]

Indian yellow was used by artist painters in both oil paints and watercolors. Due to its luminescence, it faded in darkness and artificial light, but was vivid and bright in sunlight. It was likely first used by Dutch artists, and before the end of 18th century it was commonly used by artists across Europe. Its origin was unknown until an investigation in the year 1883.

Indian yellow pigment was originally manufactured in rural India from the urine of cattle fed only on mango leaves and water. The urine was collected and dried, producing foul-smelling hard dirty yellow balls of the raw pigment.^[2] The process was declared inhumane and outlawed in 1908, as the cows were extremely undernourished, partly due to the fact that the leaves contain a mild toxin related to that found in poison ivy.

The replacement, synthetic Indian yellow hue, is a mixture of Nickel Azo, Hansa Yellow and Quinacridone Burnt Orange. It is also known as Azo Yellow Light and Deep, or Nickel Azo Yellow.

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