The city of Denver is getting more than 2,100 artworks by the late abstract expressionist Clyfford Still, to go on display in a planned museum devoted to him. The artist’s archives, however, are not part of the deal. “While the absence of the archives would have little effect on the general public’s enjoyment of the museum, it would almost certainly prevent it from becoming a world-class research facility along the lines of the Andy Warhol Museum in Pittsburgh.”