I registered on here to ask a few questions. I've seen the movie, read Twilight, watched the movie again (now that I know what happened in the book), read New Moon, and the posted draft of Midnight Sun as well as all the extras and outtakes for Twilight and New Moon on Stephenie Meyer's website.
I'm aware that my questions might be answered in the remaining books I haven't read yet, but I'm not getting them until Christmas and I would like to progress with my writing.

So, my main question:
I'm aware of the limitations on hurting vampires. Currently all I know that can hurt them are other vampires, and werewolves.
What if a vampire used a weapon? Say, a sword. Could he use a sword to pierce another vampire's body (owing to the unnatural strength of the wielder)?
The converse of that question is that the sword will shatter- it is, after all, a human creation. So my follow-up question: Do you think it is possible for a vampire to craft a weapon (let's stick with swords here) that can pierce a vampire's body? (Say by making it incredibly dense, or made of some special material... In any event, the resulting sword would not be usable by an ordinary human.)
I would appreciate any thoughts or opinions on the subject.
Thank you again for reading.