In New York, a Modigliani portrait of his wife, was sold for $15m, $2.5m up on the previous record for one of his works.

And an anonymous Middle East collector paid $3.2m for a huge cushion-shaped diamond at a sale in Geneva.

Sold for to pay for growth

Arts correspondent Razia Iqbal: "The world's most successful magazine"

The Modigliani was one of the highlights of the New York sale, by the troubled Reader's Digest organisation, to raise money for a growth plan expected to be announced next year.

Van Gogh or not? It still raised $4 million

The 38 works by impressionist, post-impressionist and modern artists including Monet, Van Gogh, Renoir, Matisse and Cezanne had been bought by Lila Acheson Wallace to adorn the offices of Reader's Digest, the magazine she founded with her husband.

The sale raised more than $86m at Sotheby's in New York.

A sculpture by Giacometti, The Forest, Seven Figures and One Head, also set a record for one of his pieces, raising $7.5m.

The Thatched Roof Cottages at Auvers went for $4.4m. The painting is attributed to Van Gogh, although some experts believe it to be a forgery, actually painted by a doctor who cared for the painter.

Despite the records, the sale was marked by caution among buyers. Most of the works sold within the pre-sale estimated range, with several barely making the low estimate or selling for even less.

Mouna sets record

In Geneva, the huge yellow Mouna diamond was bought for a record $3.2m by an anonymous Middle East collector.

The Mouna diamond on view before the sale

The Mouna diamond, fashioned by the Italian designer Bulgari, weighs 112.53 carats. It is thought to have been mined 10 to 15 years ago in South Africa.

It was the star item in a sale which earned more than $8m for Mouna Al-Ayoub, the Lebanese former wife of Saudi businessman Nasser Al-Rachid.

The sale of nearly 160 gems and pieces of modern silver was to raise cash towards the $17m refit of her yacht Phocea.