Wonader Magnet Hourglass Sand Timer Clock Glass Classic Home Desk Decor Materials:glass,magnetic,and iron filings The Magnetic Sand Hourglass is a fun desktop diversion. Flip it over and watch the grains of iron stack up in seemingly impossible formations thanks to a magnet embedded in the iron base. Watching time fly has never been so interesting!The craggy configurations of the iron filings eventually build into an ordered hemisphere with a spiky surface. Like your favorite movie, you can enjoy watching the Magnetic Sand Hourglass over and over again. Fun and creative reinvention of the traditional sand hourglass Sand is replaced with magnetic iron filings that form interesting, artistic patterns