Boxed notecards of A Sunflower from Maggie, 1937.
 
One summer morning, Georgia O'Keeffe's friend Maggie arrived at the artist's New Mexico home with the flower that inspired the painting on these cards. Once the canvas was finished, O'Keeffe traded the sunflower - the model, not the painting - to Maggie's young nephew for a stone he'd found.  She kept it on her Ghost Ranch windowsill, with the rest of her desert collections.