Hrungnir Head and Heart of Stone

Thor was eager not to let anything stop him from going to
single combat when he had been challenged to a duel, for no one
had ever done that to him before. Then Hrungnir went off on his
way and galloped mightily until he got into Giantland, and his
journey was very widely talked of among the giants, together with
the fact that an appointment had been made between him and
Thor. The giants felt there was a great deal at stake for them as to
which one won the victory. They would have little good to look
forward to from Thor if Hrungnir died, for he was the strongest of
them. Then the giants made a person at Griotunagardar of clay,
and he was nine leagues high and three broad beneath the arms,
but they could not get a heart big enough to suit him until they
took one out of a certain mare, and this turned out not to be
steady in him when Thor came. Hrungnir had a heart that is
renowned, made of solid stone and spiky with three points just
like the symbol for carving called Hrungnir’s heart has ever since
been made. His head was also of stone. His shield was also stone,
broad and thick, and he held the shield before him as he stood at
Griotunagardar waiting for Thor, and he had a whetstone as
weapon and rested it on his shoulder and he did not look at all
pleasant. On one side of him stood the day giant, whose name
was Mokkurkalfi, and he was quite terrified. They say he wet
himself when he saw Thor.


- Prose Edda, Skaldskaparmal