Technically, Xeric's Talisman is an untradeable item. However, there is a method to make money from it. All you need to do is dismantle the talisman. This will give you 100 lizardman fangs. These are tradable items. So your talisman is worth the price of 100 lizardman fangs.  If you want to use this as a money-making method, I have to disappoint you. The price of a fang is only 18 GP. So that means a 100 lizardman fangs (or one talisman) is worth 18 times 100 or 1800 GP.