Their first significant 20th-century purchases were two Fontanas a work on paper and a white painting which they selected with the help of James Kelly, a Santa Fe gallerist they've been working with since 1999.

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In 1968, a year after he finished his legendary series of black murals for his eponymous chapel at the Menil Collection in Houston and just a few months after suffering an aneurysm that nearly killed him, Mark Rothko turned to painting smaller pictures in acrylic on paper laid down on canvas.

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One of them combines painting and collage to create innocuously pretty abstractions that would make attractive wrapping paper.

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As painting became more difficult, he focused intently on the sleek, stylized paper cutouts he had first started experimenting with in the 1930s, using scissors to create the sinewy shapes and swaths of color that he could no longer render directly on canvas.

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These he transferred in light pencil onto large sheets of Arches 300-pound hot-press paper, some of them as much as six feet in length, at which point Zega set to work painting the reconstructed edifices in intense watercolor hues, taking as long as a month on each.

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