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  • In the 1910s, soon after the Curies had discovered radium, a New Jersey corporation called U.S. Radium began to mix radium with paint to create a product called Undark—radium-infused paint that emitted a greenish white light at night.

    The Emperor of All Maladies

  • Although aware of the many injurious effects of radium, U.S. Radium promoted Undark for clock dials, boasting of glow-in-the-dark watches.

    The Emperor of All Maladies

  • They were required to paint delicate lines with fine-tipped brushes, applying the Undark to the tiny numbers and indicator hands of wristwatches.

    Archive 2006-12-01

  • Undark and the Radium Girls is a damn interesting story of corporate injustice brought to us by who else?

    Archive 2006-12-01

  • You can give a guy a thrill with Undark in a much better way.”

    The Color of Silence is Radium Green


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  • Otherwit known as delight

    November 28, 2011

  • "Undark was a trade name for luminous paint made with a mixture of radioactive radium and zinc sulfide, as produced by the U.S. Radium Corporation between 1917 and 1938. It was used primarily in watch dials." (Wikipedia)

    November 27, 2011