Art shoppers came ready to spend at yesterday’s sale of Post-War and Contemporary art at Christie’s. The so-called First Open sale, which is meant to signal the opening of another art season stretching from now until the beginning of July, fired a strong warning shot. The sale had a total premium price of $10 million against a pre-sale estimate of between $7.9 million and $11.2 million in hammer prices. Overall prices came in toward the low end of estimates. There were 280 lots, and 80% of those sold. World records were set for eight artists, including Shahzia Sikander, whose “Veil n’ Trail” (1997) sold for $325,000, a far cry above the pre-sale estimate of between $15,000 and $20,000. Frank Benson, Laylah Ali, and Jonathan Meese were also among the young artists getting record-breaking bids. Established artists such as Mike Kelley, Sean Scully, Thomas Ruff, and Robert Smithson had sales well above the high estimates for their work too.