A taxi driver returned a black bag carrying 31 diamond rings to a passenger who had earlier paid him a 30 cent tip on an $11 (â‚¬8.5) ride. Hours after Osman Chowdhury, a native of Bangladesh, had dropped off the passenger, he tracked her down through a flurry of phone calls and returned the bag, which she had left in the taxi's trunk. The unidentified woman, who said she was a jeweler, offered a $100 (â‚¬77) reward. Osman reluctantly accepted the money to cover the fares he lost while tracking her down. Chowdhury told the Daily News that he never even thought of keeping the gems.