What kind of necklace is this?

The cross is primitive in looks and the etchings look like someone enhanced the surface with symbols to try and decorate it. Looks almost childlike. I would say check some books on antique jewelry for the basic design. Could be nothing at all but a piece which someone decided to decorate out of boredom because the sketches look like they were made with an awl or sharp instrument. They were not original to the piece since most of the pendent looked manufactured and the sketches did not...