I got this in a New Year's lucky bag. It's been sitting unused for two years, so I'd like to pass it on to someone who will use it. I'm not interested in it at all, and since I thought it was just a stone, I threw away the certificate of authenticity, but I think the store where I bought it (any branch) will be able to look it up. The length is 40 centimeters. I'm not interested in stones that are just for show, so I've never used it. Color: Yellow