In November 2006 the Lempertz auction house in Cologne sold Rotes Bild mit Pferden, Red Picture with Horses, for 2.4 million euros. It was said to be a work of 1914 by Heinrich Campendonk. In fact it was a forgery by Wolfgang Beltracchi. The paint contained traces of titanium white, a pigment first developed in 1935. Beltracchi had used a ready-made tube of zinc white that contained it. In October 2011 he was sentenced to six years in prison and his wife to four. The police identified 100 paintings that he had most likely forged.
For decades his forgeries had passed recognized experts and auction houses. A material analysis exposed them.