Emmanuelle Alt, the editor-in-chief of Vogue Paris, once said, “I’ll stop wearing black when they invent a darker colour.” Well, it might be time for her to visit Harvard’s museum of rarest colours, the Forbes Pigment Collection.

From the emerald green used in Van Gogh’s paintings to Cochineal extracted from squashed beetles, each of the 2,500 rare pigments in the library has an unlikely story to tell.

But it is India which lends this library its rarest colour. The video above tells the story of how Indian Yellow is extracted, and why it was outlawed in 1908. Cows and mangoes were involved.

The most unusual pigments come from beetle extracts, poisonous metals and even Egyptian mummies. The video below chronicles some of the colours in this museum.

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Many times these colours have been used by curators and art conservators to authenticate classical paintings. For instance, a supposed Jackson Pollock painting “rediscovered” in 2007 was identified as a fake after pigment analysis. A specific shade of red used in the painting was found to have been manufactured 20 years after the artist’s death.

A number of debates about the ownership of these colours keep circling around. British artist Anish Kapoor was banned for using the pinkest of pinks by its creator Stuart Semple, who made the “pinkest” pink in protest after Kapoor was granted exclusive rights to the “blackest black” in 2014.

In the video below, Semple talks about what led to the fight.

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