How much did Jackson Pollock 's piece " Blue Poles : Number 11 , 1952 " sell for at auction in 1973 ?
In 2012 , " Number 28 , 1951 , " one of the artist ’s combinations of drip and brushwork in shades of silvery gray with red , yellow and shots of blue and white , also sold at Christie 's , New York , for $ 20.5 million — $ 23 million with fees — within its estimated range of $ 20 million to $ 30 million .