Trivia: At the beginning, the cabin looks very similar to the cabin in The Evil Dead, even the swinging bench (although on the opposite side of the door). And the girl calls out the name Ashleu, Bruce Campbell's character in Evil Dead.
Trivia: At The End of the episode, Dean says to Sam "hey did she look familiar?" Then says "are you hungry? I could go for some pea soup." He's referring to Linda Blair in the Exorcist. She played a cop in this episode.
Answer: Angel blades come from angels. It's their angelic magic that makes it special. Therefore, an archangel blade is made magical with the powers of an archangel. They couldn't have just created one or used one, as none of them are archangels.