LONDON.- Sales of important private collections have always been the lifeblood of the art market, returning long-hidden material into circulation and also serving as a fascinating permanent record of the taste and eye of an individual collector. In the Old Master field at least, such sales are rather less frequent now than in previous generations, so they are ever more eagerly awaited by private and institutional buyers alike. Formerly owned, in many cases, by leading collectors of the 18th and 19th centuries, several drawings in this exceptional and very personal collection also featured in great sales of the past – including the famous Chatsworth and Holkham Hall auctions. Assembled with great care and discrimination over a quarter of a century, this excellent collection consists primarily of Italian drawings from the 16th-18th centuries. One of the early highlights is the superb study of a standing female figure by Parmigianino (est. £120,000-180,000), made in 1531-9 in