Thanks to
Writtenwrydd for pointing out this hugely interesting article by Michael Briggs, husband of
Patricia Briggs, on silver and how it can be used (but not without a LOT of effort) to make silver bullets.
Silver Bullets
"[P]rior to the industrial revolution, there was insufficient sulfur in the atmosphere to tarnish silver."
"Because some organic poisons contain high concentrations of sulfur, it was found that poisoned food or wine could blacken silver on contact, leading to the widespread custom of drinking from silver cups, or eating with silverware."