Raphael's Tourmaline Tongs

Chapter 6, verses 5 to 7 of the biblical Book of Isaiah tells of a vision by the book’s title character, in which he objected that he could not be a prophet because he had unclean lips. At this, an unnamed angel-later identified with the archangel Raphael-took a glowing coal from the altar of sacrifice with a pair of tongs and used it to cleanse Isaiah’s lips, rendering them clean and meet for prophecy.