Heron mark

From A Wheel of Time Wiki

During the Age of Legends, Aes Sedai created weapons with the Power. Some were swords, and some of these blades were marked with a heron. Heron-mark blades are awarded to Blademasters as a symbol of their skill. Some Heron-mark blades were made by blacksmiths after Aes Sedai started taking Oaths to not create weapons.

In The Great Hunt^{[need reference]} Rand Al'Thor is confronted by Ba'alzamon while searching for the Horn of Valere. While holding his sword Ba'alzamon heats the sword and Rand is branded on his hands with herons.