Wednesday evening marked the end of December's Old Master and British painting auctions in London, where the three major sales at Christie's, Sotheby's, and Bonhams brought in over £50 million ($78 million) — revealing a robust yet selective market with high demand for work by 17th-century Dutch and Flemish artists. On the whole, there were high buy-in rates, but the works that did sell often went for prices that far surpassed estimates.

The sales began on Tuesday evening at Christie's, where the auction house brought in £24.2 million ($37.6 million) — at the high end of its £18.2-26.5 million pre-sale estimate. A 1798-9 Francisco José de Goya y Lucientes  portrait of Phillip II's court embroiderer, failed to sell on an estimate of £4-6 million ($6.1-9.2 million), but otherwise the sale was a tremendous success. Sell-through rates were a respectable 72 percent by lot and 79 percent by value, with 73 percent of the works that sold going above-estimate.

The top lot ended up being Pieter Bruegel the Younger's "The Battle Between Carnival and Lent." Bidding blasted through the £3.5-4.5 million estimate for the painting — one of several studies that the younger Bruegel did of his father's 1559 masterpiece of the same name — to hammer down at £6.9 million ($10.7 million), setting a record for the artist. Rounding out the top three were Willem van de Velde II's maritime painting "Dutch Men-o'-War and Other Shipping in a Calm," which sold for £5.9 million ($9.2 million), tripling its £1.5-2.5 million estimate, and a recently rediscovered 1646 portrait by Govaert Flinck, a student of Rembrandt. "An Old Man at a Casement" found a buyer at £2.3 million ($3.6 million), well ahead of its £700,000-1 million estimate. Both sale prices set records for the artists at auction.

At Bonhams the next afternoon there was a mix of wildly overperforming prices — and an abundance of unsold work. While only 32 of the 62 offered lots found buyers, making for a sell-through rate of 52 percent by lot, the sell-through rate by value was a remarkable 92 percent. The star of the afternoon was a Diego Rodriguez de Silva y Velazquez portrait that the auction house stumbled upon last year during the sale of little-known 19th-century British painter Matthew Shepperson's collection. It was analyzed extensively by Peter Cherry — an authority on the Spanish master — and found to be authentic. The painting fetched just under £3 million ($4.7 million), at the high end of its £2-3 million estimate ($3.2-4.8 million).

In a more unexpected turn of events, Adriaen Coorte's 1693-95 still life "Three Peaches on a Stone Ledge With a Painted Lady Butterfly" also passed the £2 million ($3.2 million) mark. The work, estimated to sell for £300,000-500,000, set an auction record for the Dutch artist, who specialized in small, simple still lifes that often contained just a few objects.

At the £20.1 million ($31.4 million) sale at Sotheby's Wednesday evening (est. £17.6–24.2 million, $27.5-37.9 million) 12 of 38 lots were passed up, making for a 68 percent sell-through rate by lot. However, the rate by value was a lofty 90 percent — meaning that many of the paintings that did sell achieved prices higher than expected.

As predicted, the highest price paid at the auction was £6.8 million ($10.6 million) for a pair of group portraits known as "conversation pieces" by German-born artist Johann Zoffany. Zoffany was good friends with the British actor David Garrick, and these two paintings depicted him and his family at their estate near Hampton Court, just outside of London. The pre-sale estimate on the duo was £6-8 million.

Just below the top lot was a 1660 Dutch interior painting by Jan Steen — the artist's masterpiece, according to Sotheby's — which depicts several people playing cards. The £4.9 million ($7.7 million) total set a record for the artist at auction, though it fell at the low end of the £4.5-6 million ($7-9.4 million) estimate.