Roy Lichtenstein’s €1,000 painting now valued at €50m

Art auctions at Christie’s and Sotheby’s in New York expected to net between $2bn and $2.5bn

Combined estimates for the May series of Impressionist, Modern and Contemporary Art auctions at Christie’s and Sotheby’s in New York are, astoundingly, between $2 billion and $2.5 billion. Records are likely to be smashed.

Most attention will be on Christie's where, on Monday night [May 11th], Picasso's painting Les femmes d'Alger (Version "O") is estimated at $140 million and Giacometti's sculpture L'homme au doigt (Pointing Man) is estimated "in the region of $130 million" – both potentially new world record prices at auction for painting and sculpture.

There are numerous paintings with estimates in the tens-of-millions of dollars category in Christie's. Portrait of Henrietta Moraes by Dublin-born artist Francis Bacon, is estimated "in the region of $35 million"– it last changed hands just three years ago for $33.4 million.

Another female nude, titled Benefits Supervisor Resting, by Lucian Freud is $30million-$50 million.

At Sotheby's, on Tuesday, Mark Rothko's Untitled (Yellow and Blue), estimated at $40 million- $60 million, dating from 1954, is described as a painting "standing at over eight feet tall" that "engulfs the viewer in the vastness of its yellow and blue planes".

Rothko was a Russian-born, American painter who died in 1970. Sotheby’s said “the work stands as a towering thesis on the absolute limits of abstraction with the seamless flow of colour and light emanating as if from within”.

But perhaps the most astounding of the many multi-million dollar estimates is for a 1960s American "Pop Art" painting: The Ring (Engagement) by Roy Lichtenstein, estimated "in the region of $50 million" at Sotheby's. The 4ft by 6ft painting, described as a "comic book masterpiece", was sold for just $1,000 when it was completed by the artist in 1963.

It's being sold, Sotheby's said, by Chicago businessman and philanthropist Stefan T Edlis, who said: "Having amazed me from the moment I saw it, I find The Ring as beautiful today as it was all those years ago.

“We have lived with this iconic painting for nearly 20 years and hope it brings as much pleasure to the new owner as it has to me and my family.”