Midrash for Kiddushin 42:23

(Devarim 15:17) "Then you shall take the awl and place it": Whence is it derived that also valid for this purpose are thorn, glass, and reed haulm? From "then you shall take" (anything that lends itself to "taking." These are the words of R. Yossi b. R. Yehudah. Rebbi says: Just as an awl is distinct in being of metal, so all that are of metal (may be used).