St. Christopher medallion - so yes it is a pendant.
Not a coin nor token nor medal - just worn for good luck. He is the patron saint of travellers.
I have one - here are both sides (notice the four modes of transport on the back) ...
I have a different pin type version of a St. Christopher's medal as well. Found it with a metal detector. It is silver tarnished black, and if you look closely, ZacUK, you will see the four modes of travel as well. In the top right position is the air travel of the day, a Zeppelin! Photo attached.