Sotheby's saw a $117.1m (£74.6m) hammer total at their evening sale on November 11, above the $69m-99m pre-sale estimate and following on from their $197m (£120m) evening auction of Impressionist and Modern art the week before.
They sold arguably the most important Andy Warhol (1928-1987) left in private hands - 200 One Dollar Bills, from his first series of silkscreen paintings made in 1962.
It saw some sensational saleroom action. Estimated at $8m-12m, auctioneer Tobias Meyer opened at $6m, but a bidder in the room immediately jumped in at $12m. Five further bidders carried it upwards, until it was knocked down at $39m (£24.8m) to an anonymous buyer on the telephone.
This was the second highest price for the artist, but still some way behind Green Car Crash (Green Burning Car I) from 1963, which sold for $64m (£33.9m) at Christie's New York as the contemporary art market approached its zenith in May 2007.
Sotheby's saw further works by Warhol, Jasper Johns (b.1930), Jean Dubuffet (1901-1985) and Willem de Kooning (1904-1997) all went over $5m, and only two of the 54 lots were unsold.
Christie's evening sale of contemporary art in New York on November 10 made $63.9m (£40.7m) hammer against pre-sale hopes of $61.5m-88m. Of the 46 lots, 39 got away, although the two potential stars, Brother Sausage by Jean-Michel Basquiat (1960-1988) estimated at $9m-12m and Warhol's Tunafish Disaster estimated at $6m-8m, both failed to sell.
However, the top lot brought strong bidding. Peter Doig's (b.1959) Reflection (What Does Your Soul Look Like), estimated at $4m-6m, saw five parties compete for it, including Jay Jopling of the London dealership White Cube. It sold to an anonymous telephone bidder at $9m (£5.73m).
The Christie's sale also included Jeff Koons' (b.1955) wooden sculpture Vase of Flowers from a 1991 edition of three. Unusually since the downturn, the vendor - reportedly the publisher Benedikt Taschen - had been given a guarantee either by Christie's or a third party.
Having last sold at auction at Christie's in London in June 2000 for a premium-inclusive £663,750, here it was estimated at $4m-6m and sold to anonymous buyer for $5m (£3.18m)
Christie's contemporary art day sales made a combined $36.1m (£23m), while Sotheby's took $36.2m (£23.1m) for their equivalent sale.
When added to the Impressionist and Modern series, this meant the final total generated by the big two for the fortnight of sales in New York was $513.28m (£326.9m). This was down from $635m (£423m) at last year's equivalent sales.
By Alex Capon
£1 = $1.57