speaking of folktales, only a 'silver bullet' can penetrate through werewolf's skin... :)

What we understand as vampires and werewolves are revised versions of several separate folk tales. So the stories vary, depending on what werewolves and vampires can actually do, and what their weaknesses are. Good to remember. ;) My guess is that silver is a valuable metal, and its purity works against the "corrupt" nature of vampires and werewolves. I had a look, apparently the silver bullet story might come from the beasts of Gévaudan: these were apparently wolf-like creatures which terrorised France in the 18th century. The second one was shot and killed with silver bullets.

actually this vampire-silver thing is pretty unusual. blood ties was the first production where i heard that vampires seem to react a little 'allergic' to silver :D in the buffy era there was no such thing like it could have killed a vampire. i remember that, besides that holy thingie that cowboy already mentioned, silver is said to clarify the blood. it has some antibacterial characteristics. that's why silver is used for real-life medical purposes, too.

because silver was thought to be a holy metal. cowboy...