Johannes Vermeer’s 'Girl with a Pearl Earring' is often called the 'Mona Lisa of the North.' Recent scientific analysis of the painting has revealed secrets that remained hidden for centuries. In 2020, researchers using macro-X-ray fluorescence scanning discovered that Vermeer had originally painted a green curtain in the background, which has since faded to a dark, featureless black due to chemical changes in the pigments. They also found that the girl originally had tiny eyelashes, which were later worn away by time and cleaning. Most famously, the 'pearl' itself is likely an illusion of light; it has no hook to attach it to the ear and is composed of just a few clever dabs of white paint. Vermeer's mastery of light and shadow is what gives the jewelry its luminous, realistic quality.