phony

It's the backstory of phony that deserves our attention. Phony (which dates from the early 1900s) is believed to be an alteration of the British fawney, the word for a gilded brass ring used in a confidence game called the "fawney rig." In this game, the trickster drops a ring (or a purse with some valuables in it) and runs to pick the item up at the same time as the poor sap who notices it on the ground. The trickster asserts that the found treasure should be split between them. The one who's "found" the item, convinced now of its value, chooses instead to give the con artist some money in order to keep the item, which is, of course, phony.