What happens when undisclosed lead glass–filled rubies enter the market? Here’s how retailers can avoid disastrous results.Within the past year, Leo Anglo, the general manager of Vincent’s Jewelers in St. Louis, has seen so many customers carrying rubies through his doors that a rush on the classic gems appears to be in full swing.There was the colonel in the Armed Forces who brought in eight oval-shape rubies he’d bought from an Army and Air Force Exchange Service–approved vendor in Afghanistan for about $600 a carat ($5,000 total), and the woman who’d paid $1,700 for a 0.75 ct. ruby in a 14k gold mounting at a national department store.The problem? Neither client had been told the stones were lead glass–filled and required special care. Anglo had the unenviable task of delivering the bad news: The stones weren’t worth anywhere near what the customers had paid for them.