What Legend Is The Basis Of The Story "The Weirdstone Of Brisingaman"�?

This fantasy novel by Alan Garner is based on an ancient Norse myth. The Brisingamen was a magical golden necklace made by a group of dwarf craftsmen called the Brisings. Freya, the goddess of love, lust and fertility, longed so desperately to possess this necklace that she agreed to sleep with each of its four owners to gain it. She got the necklace, but Odin, chief of the gods, was so disgusted with her behaviour that he sent her to Midgard (our world, the origin of Tolkien's Middle Earth) where she stirred up war and divided the bodies with Odin.

Despite Odin's anger, Freya continued to love and wear the necklace, which made her more beautiful than the stars (it was supposed to represent the stars). It became so much a part of her that she lent it to Thor when he wished to disguise himself as her, on a later mission.