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Prussian Blue: An Accident, Then an Antidote

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Katsushika Hokusai's Under the Wave off Kanagawa, around 1830-32, printed with the newly imported synthetic pigment Prussian blue mixed with traditional indigo, from the Metropolitan Museum of Art's collection

The collection

72 works · newest first

  1. Jacques-Louis David's The Death of Socrates, 1787, showing Socrates reaching for a cup of hemlock while still gesturing upward as if teaching, surrounded by grieving disciples, with Plato seated and slumped at the foot of the bed. Painting The Death of Socrates: The Man Who Wasn't There A Hellenist scholar advised David on staging a mourner who, by his own account, wasn't in the room. The Met's 2022 X-ray study shows how deliberate that choice was.
  2. Resources The Open-License Museum Image Directory: Where to Find Art You Can Actually Use Ten major museums and archives that release collection images under an open license, checked against each institution’s own current terms page: what’s actually free to use, what still requires attribution, and the one major outlier that isn’t cleared for commercial use.
  3. Masaccio's Holy Trinity fresco, 1425-1428, in Santa Maria Novella, Florence, showing a coffered barrel-vaulted chapel painted in single-point perspective with all orthogonal lines converging toward one vanishing point below the figures. Technique Nobody Alive Saw the First Vanishing Point Brunelleschi's two demonstration panels are lost, scholars can't agree what year he built them, and the one detailed account of how they worked was written decades later.
  4. Rembrandt van Rijn's The Anatomy Lesson of Dr. Nicolaes Tulp, 1632, showing Dr. Tulp holding forceps over the dissected left forearm of the corpse while seven members of the Amsterdam Guild of Surgeons look on. Painting The Anatomy Lesson of Dr. Nicolaes Tulp: Retested A 2006 study found four anatomical errors in Rembrandt's dissected forearm painting. A 2026 retest, run by one of the same researchers, cleared three of the four.
  5. The full ceiling of the Sistine Chapel, painted by Michelangelo between 1508 and 1512, showing the Genesis scenes and surrounding prophets and sibyls. Painting Michelangelo's Sistine Chapel Painting: 'It Is Not My Art' Michelangelo painted the Sistine Chapel ceiling standing upright for four and a half years, not lying down, and built his own scaffold after rejecting the pope's design.
  6. Narcissus, oil on canvas attributed to Caravaggio or, in a rival attribution, to Giovanni Antonio Galli (lo Spadarino), showing an adolescent boy in a brocade doublet kneeling over water and reaching for his mirrored reflection. Painting Who Really Painted Caravaggio's Narcissus? Longhi attributed it to Caravaggio in 1916. A 1986 case for a different painter, the obscure Spadarino, still divides scholars, and a 1995 X-ray restoration didn't settle it.
  7. Leonardo da Vinci's Mona Lisa, oil on poplar panel, in the Musee du Louvre, showing the soft, gradually blended tonal transitions around her eyes and mouth that define the sfumato technique. Technique Art Techniques: What Conservation Science Found Sfumato, impasto, and pointillism get one-line definitions. X-ray fluorescence, a rheology study, and Seurat's own reading list measured what those lines leave out.
  8. Claude Monet's 1872 painting Impression, Sunrise, the canvas a hostile 1874 review mocked by name and unintentionally gave Impressionism its label. Movements Art Styles: The Movement Names That Started as Insults Impressionism, Fauvism, and Cubism all began as a critic's put-down. Baroque and Gothic carried the insult even longer before scholars made the names official.
  9. Rene Magritte photographed by Lothar Wolleh, wearing a dark coat and bowler hat against a plain background. Painting The Lovers Painting Is Actually Two Different Canvases MoMA and the National Gallery of Australia both own a painting called The Lovers, made by Magritte in Paris in 1928. Their ownership records look nothing alike.
  10. Piero di Cosimo's posthumous portrait of a woman, said to be Simonetta Vespucci, shown bare-shouldered in profile with a small snake coiled around her necklace and a stormy landscape behind her. Painting Simonetta Vespucci: A Death Reopened by Medicine A 2026 medical paper argues a pituitary tumor killed Botticelli's presumed muse at twenty-three, though scholars still cannot agree she is in the paintings at all.
  11. The Empress Theodora mosaic in the Basilica of San Vitale, Ravenna, showing Theodora in jeweled robes and a gemmed crown flanked by attendants and clergy, made around 547 AD. Decorative Arts Why the Best Byzantine Mosaics Survive in Italy Hagia Sophia's original gold mosaics were destroyed in the Iconoclasm. The best 6th-century survivors instead sit in a Ravenna church that had already left Byzantine rule.
  12. Jules Bastien-Lepage's 1879 painting Joan of Arc, showing the peasant girl in her parents' garden reaching toward the faint, transparent figures of three saints who appear to her among the trees. Painting The Joan of Arc Painting One Critic Called False Bastien-Lepage's 1879 Joan of Arc won praise for its heroine's pose, but one critic called its ghostly saints 'false naturalism.' An American bought it for the Met.
  13. The Milkmaid by Johannes Vermeer, showing a maid in a plain kitchen pouring milk from a jug into a bowl on a table set with bread. Painting Vermeer's Milkmaid: What the X-Rays Keep Finding Vermeer's Milkmaid outsold every painting but one in 1696. In 2022, Rijksmuseum scans found he'd painted over a jug holder and a fire basket, and sketched in a hurry.
  14. Jackson Pollock's passport photograph, taken July 21, 1955, roughly three years after he painted Convergence and about a year before his death. Painting Jackson Pollock's Convergence, Sold as a Puzzle Critics called its reds an 'unfortunate' clash. Springbok later turned Convergence into the 340-piece jigsaw marketed as the world's hardest puzzle.
  15. Egon Schiele's 1912 watercolor of his Neulengbach jail cell, showing a single orange on a blanket beside a folded jacket used as a pillow. Painting Egon Schiele: The Kidnapping Charge Was Dropped, the Conviction Wasn't Neulengbach police charged Egon Schiele with kidnapping a runaway teenager in 1912. The charge collapsed, but a separate immorality charge still sent him to jail.
  16. John Martin's The Great Day of His Wrath, an 1851-1853 oil painting at Tate Britain showing a mountain citadel collapsing under a dark, stormy sky. Painting John Martin's Paintings: A Blockbuster the Academy Rejected John Martin's paintings drew paying crowds and got pirated as an unauthorized diorama in 1833. The Royal Academy still rejected his last trilogy as vulgar.
  17. John Everett Millais's 1851-52 painting Ophelia, showing Elizabeth Siddal as the drowning Shakespearean heroine floating amid wildflowers in a river, now held at Tate Britain. Painting Ophelia: The Sitting That Nearly Killed Its Model, and Cost £50 Millais's lamps went out while Elizabeth Siddal posed as Ophelia in a freezing bathtub. She caught pneumonia, and her father billed Millais £50 for the doctor.
  18. Lucas Cranach the Elder's chiaroscuro woodcut Saint Christopher, inscribed 1506 but dated by the Cleveland Museum of Art to probably after 1508. Technique Chiaroscuro Woodcut: The Inventor Backdated His Own Print The Cleveland Museum of Art dates Cranach's inscribed-1506 chiaroscuro woodcut to after 1508, once he had learned the tone-block technique from a rival.
  19. Kazimir Malevich's 1915 painting Black Square, a black square with a fine white border, hanging in the Tretyakov Gallery in Moscow. Movements Monochromatic Painting: What's Hiding Under the Black Square X-rays found two paintings and a disputed inscription under Malevich's 1915 Black Square. Klein never patented his blue, and Reinhardt's black held three different tones.
  20. A girih tile geometric pattern on a spandrel from the Darb-i Imam shrine in Isfahan, Iran, built in 1453, bordered by a Kufic calligraphy band, the tiling that physicists Peter Lu and Paul Steinhardt cited as evidence of medieval quasicrystalline design. Decorative Arts Pattern in Art: A 1453 Tiling That Beat Physics by Five Centuries A 15th-century Isfahan tiling matches a geometry physicists could not formalize until the 1970s. Whether it is truly a quasicrystal is still disputed in print.
  21. The Birth of Venus by Sandro Botticelli, showing the goddess standing on a giant scallop shell as Zephyr and a companion blow her toward shore and a robed figure holds out a flowered cloak. Painting The Birth of Venus: The 1499 Inventory That Doesn't Mention It No document records who commissioned The Birth of Venus. A 1499 household inventory, unpublished until 1975, lists its companion painting and leaves this one out.
  22. The Venus de Milo, an armless marble statue of a partially draped woman, on display at the Louvre. Sculpture Venus de Milo: The Signed Base the Louvre Never Displayed A fragment found with the Venus de Milo named its sculptor and dated it later than the Louvre's director claimed. The fragment went missing soon after.
  23. David Alfaro Siqueiros, photographed by an unknown photographer circa 1922-1924, roughly a year before he helped found the Mexican muralist movement's painters' union. Painting Famous Mexican Artists: The Muralist Who Led a Raid on Trotsky's House David Alfaro Siqueiros ran a workshop that shaped Jackson Pollock, then led an armed raid on Leon Trotsky's villa. A judge acquitted him of the worst charges months later.
  24. Solomon R. Guggenheim, his wife, Hilla von Rebay, and Wassily Kandinsky photographed together in the Bauhaus garden in Dessau in 1929, during the trip that deepened Rebay's push to build Guggenheim a non-objective art collection. Movements Non-Objective Art: The Curator the Guggenheim Wrote Out of Its Name Hilla Rebay named a Guggenheim museum after this term in 1939 and picked Frank Lloyd Wright to build it a home. She was pushed out in 1952, before either one survived her.

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Dates, attributions, dimensions and locations here come from the institution that holds the work, with its collection page cited so you can check. Where scholars disagree, the disagreement is reported rather than smoothed over. About UmberLore

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