Pierre Bonnard, Nu en Hauteur, 1906.

Art collector and dealer Giuseppe "Joe" Nahmad died Nov. 23 in Monte Carlo, Monaco. Born in Aleppo, Syria, in 1932, Nahmad was known for his lucrative 55-year career buying and selling modern art. Together with his brothers and business partners, David and Ezra, Nahmad built a collection estimated in 2007 by Forbes to be worth $3–4 billion.

Specializing in 19th- and 20th-century art, Nahmad amassed a fortune selling work by such heavy hitters as Monet, Braque and Rothko. Nahmad opened his first art dealership in Milan in 1957, and established a successful business just as the city was becoming a global art capital. His collection includes perhaps the largest single holding of art by Picasso outside of the artist's family, according to Forbes, with 300 works valued at $900 million dollars. Nahmad's nephews now run Helly Nahmad Gallery in New York and London.

The extensive art holdings of the Nahmad family are housed in part at a tax-free facility at the Geneva airport, which holds 4,500-5,000 pieces, according to a statement from their press representatives. The contents of this vault are largely a secret, although the Nahmads did allow their collection to be the subject of an exhibition at the Kunsthaus Zürich in 2011. The collection will make its second public appearance at the Grimaldi Forum, Monte Carlo, in an exhibition set to open July 11, 2013.