Few major American artists have been as productive, for so long, in so many media, as Georgia O’Keeffe was during her extraordinary career. From her early, accomplished drawings—which caught the eye of her future husband, Alfred Steiglitz, in 1916—through her firm studies of urban life and architecture in the 1920s and well into her gorgeous later works inspired by the natural beauty of New Mexico, O’Keeffe forged a unique, solitary path through the landscape of modern art.
Born during the year of Queen Victoria’s Golden Jubilee (1887), the span of O’Keeffe’s life (she died in 1986, at 98, in New Mexico) seemingly encompassed not mere decades, but ages: the invention of the airplane, two world wars, the Cold War, the Space Race and the introduction of the personal computer. So much of her work—the huge flowers; the sun-bleached skulls; the brilliant, near-abstract nature studies; the sensuous pottery—is so distinctive that categorizing her, or placing her in one school or another, is impossible.
If any artist ever followed her own vision, no matter where it took her, it was O’Keeffe.
Here, LIFE.com looks at a single photograph—John Loengard’s astonishing 1967 portrait of the artist as an old woman—that somehow manages to suggest, in one frame, Georgia O’Keeffe’s willful isolation, her breathtaking self-possession and her singular place in the American consciousness.
Loengard’s unforgettable picture—made on the roof of O’Keeffe’s Ghost Ranch home in northern New Mexico—is far more than just a study, or a sketch, of a formidable figure. Framed against the sky and desert, seated before a chimney that feels, in its simplicity, almost totemic, the black-clad O’Keeffe seems carved into the photograph, as much a part of the severe Western landscape as the rocks, sand and sagebrush that surrounded her. She might have been sitting there for an hour, or for a thousand years.
Of the many, many fine—and not infrequently iconic—portraits that LIFE magazine published through the years, Loengard’s picture of O’Keeffe is one of the very greatest.
In a March 1968 cover story on O’Keeffe (Loengard’s rooftop portrait graced the issue’s cover), LIFE devoted more than a dozen pages to the artist, hoping to illuminate for its readers what the magazine called “the interlocking of her life and art”:
TIME’s Richard Lacayo, meanwhile, had this to say about O’Keeffe on the occasion of a major 2009 show of her work at the Whitney in New York:
Freedom—from cliché, from stasis, from the expected and the tame—has always been the aim and the spur of the greatest artists. In Loengard’s elemental portrait of a woman who long ago slipped the bonds of convention, that freedom is seen for what it truly is: sober, essential, invincible.
Ben Cosgrove is the Editor of LIFE.com