I've seen Mark wearing a necklace with what looks to be a small white claw through the episodes, then Olly was wearing one also last episode! Just wondering what the necklaces are made of and the significance?

Hey there brewke!

I could be wrong, but Olly sort of answered this question on his website oliversteeds.com - Mark's is the dog tooth necklace he got from the Kombai. I'm not sure if Olly's is also his gift from the Kombai or not, though.