Postby ValkyrieVixen » Thu Jan 21, 2010 1:19 pm
It wouldn't likely be a number in the center. Maybe try a pencil rubbing to see if the rest of the mark shows on the paper.
These stones are frequently called Jade or Green Onyx but most often are made of glass. Mexican Jade isn't actually Jade but dyed Travertine. I have never seen real Jade used in Mex jewelry. There may be pieces out there but most pieces sold as Jade are not.