In the 20th century Colnaghi, under a succession of expert directors, became renowned for its Old Master drawings.

ECONOMIST: Dealing in Old Masters

Clearly, Old Master drawings are not always such a bargain.

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When Lugt died in 1970 at the age of 86, on Rembrandt's birthday (July 15th), the foundation held 6, 000 Old Master drawings, thousands of etchings and artists letters, as well as the miniatures and frames.

ECONOMIST: A collection that��s well worth a visit

"In the auction context, this is really the most intensely moving, powerful and wonderful drawing that we have ever had, " Gregory Rubinstein, Sotheby's head of Old Master drawings, said in an online discussion of the work with other Sotheby's specialists.

WSJ: Collecting: Treasures With History

The collection spans a range of styles and eras, including old master paintings and drawings, rare works by impressionist greats, African art and more.

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