An Athame is quite new to witchcraft; since Gardner/Crowley. The old witch,from ancient times, would only use a knife for cutting the stems of herbs,if the stems were to be used in a potion.They would not use the knife for any other purpose as it might "spoil" the magic of herbs. But it would be just an ordinary knife; not used in any ceremony or ritual.
My teacher formed a "protective" circle using her finger. I still do!
However, a sword has from long ago thought to have "magical" powers.