This week, Sotheby's held an exceptionally successful modern art sale at which 52 of the 54 lots sold, raising $134.4m against the expected total of $97.7m.

Most of the difference between these two figures can be accounted for by looking at a single lot, however: an early Andy Warhol piece, using his favourite silkscreen inks.

The piece shows black-on-grey life size $1 bills in regular rows and columns. It was no surprise that it turned out to be top lot, having been estimated at $8-12m, but even this figure rapidly started to seem absurd as the bids mounted up.

Excited bidding pressed up past the $20m, $30m and even $40m to sell for an immense $43.8m in front of a startled crowd.

You can see the sale on video here: http://www.youtube.com/watch?v=EImrppu5m4Y

The name of the new owner is unknown, as they took part through telephone bidding. The seller, however, is believed to be London-based collector Pauline Karpidas, who must be celebrating.

Warhol remains an iconic figure in the art world and his work and IMAGE_are highly sought after. He remains on the Top 10 Dead Celebrity Earners list and is the subject of a major exhibition at Milwaukee Art Museum until January. One of his portraits of Michael Jackson recently sold for over $1m

Andy Warhol's self portrait

Other Warhol works in the sale also smashed their estimates:  an Untitled work using pencil, felt tip marker and graphite to show a roll of dollar bills sold for $4.2m, ahead of its original estimate of $2.5-3.5m.

Likewise a huge self-portrait by the artist in acrylic and silkscreen ink on canvas, dated 1965 and inscribed to Cathy, crushed its valuation of $1-1.5m to be taken home for $6.1m.

A real show of growing vigour from the modern art market.