I metal crucifix when you open the back there is wood in it .i got it from my dad he got it from his mom .?

i metal crucifix when you open the back there is wood in it .i got it from my dad he got it from his mom and she got it from her dad . i don't know how old it is . its a crucifix that you can have around your neck . i was looking at it and there is very small screws in the back and when you undo them there is 5 small pieces of wood 3 going from the top to the bottom and 2 on the right and left side . i cant find any info about it . please help.