.... Just need to point this out - those are absolutely not Tibetan. Those are Norse runes and, ahem, one of the example talismans actually says "Odin" on it.
Aside from that particular inaccuracy they're actually great amulets; the same ones are for sale at my local pagan shop and they work wonderfully.
Assuming those really are the same ones my shop carries (and they look absolutely identical, so I assume they are), they are specifically made from yak bone.
Thanks, uh, whoever will take care of this!