Pasture
I am the only National Wonder to grant an automatic instantaneous victory. My popular name isn't the first name by which I was known.
Only metals that I'm aware of that can give culture with a religious belief are silver and gold, but I thought you already said no to them.
Is the answer Oxford University?
Ah. 24 hours is a long time to wait <pout>.
Clue#1: I can yield culture, but only with the appropriate religious belief.
Clue#2: I'm a metal.