Your Floor Can Glow in the Dark with Luminescent Gravel

Ever wanted to create luminescent designs or safety arrows in your floor, but weren't too crazy about those crappy, glow-in-the-dark stickers? Now a company in the Netherlands called Hidden Safety is marketing luminescent gravel, which can be mixed into concrete floors to create beautiful patterns or just point people the right direction in the dark. The gravel looks ordinary in light, but it is actually absorbing photons (hence, the material is often called photoluminescent). When darkness falls, photons zoom out of the gravel and create a glow. More »