The beauty industry is home to a slew of gadgets: LED face masks, at-home IPL systems, and facial cleansing brushes, to name a few. But what’s recently made waves for its ease of use, de-puffing powers, and oh-so-Instagrammable aesthetic are face rollers. Usually made out of crystals (think: rose quartz or jade), face rollers are handheld gadgets that are used to roll the face. They’ve become an essential (and often...