Tucked away inside a limestone cave in southeastern France lies some of the oldest artwork in existence. Known as Chauvet Cave, the site is so historically important—and fragile—that its location is kept secret and the cave is locked behind a huge steel door. And now, researchers have devised a technique to safely investigate these artworks and understand the natural varnish that has protected them for centuries. Their findings are published in the journal ACS Omega. ...read more read less