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In page Rubia tinctorum:

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The chemical name for the pigment is alizarin, of the anthraquinone-group, and was used to make the alizarine ink in 1855 by Professor Leonhardi of Dresden, Germany. In 1869, the German chemists Graebe and Liebermann synthesised artificial alizarin, which was produced industrially from 1871 onwards, effectively ending the cultivation of madder. In the 20th century, madder was only grown in some areas of France.