This ca. 1821 portrait of John Adams by Gilbert Stuart hangs in the National Gallery of Art in Washington, DC.
This likeness was painted when the second president was in his eighties. However, Stuart copied it from a much earlier National Gallery picture, the portrait of Adams he began from life studies in 1800. -- NGA
The National Gallery of Art says this of the Gibbs-Coolidge portrait of Adams:
This portrait is a version of the one that Stuart began of John Adams in 1798 and completed in 1815, which is also in the Gallery's collection [1954.7.1]. Adams (1735-1826) was second president of the United States. Stuart changed the color of the suit to a rich reddish brown, raised the collar, and omitted Adams' hand. Like the portrait of Jefferson [1986.71.1], it has touches of blue around the eyes, and blue tones are found elsewhere in the face. It may have been painted in September 1821 after Adams sat for Stuart to permit the artist to touch up the version that had been made for John Doggett. John Quincy Adams noted this sitting of “two or three hours” in his diary on 27 September, adding that “Stuart paints this picture for a Mr. Doggett, as one of the five Presidents of the United States. He is to paint them all for him.” -- NGA