A boar whose bristles are gold and glow in the dark, running over sky and water faster than any horse: Gullinbursti („golden-bristle"), the mount of the fertility god Freyr.
Gullinbursti (also called Slíðrugtanni) was made in the famous smithing wager of the dwarves: Sindri and Brokkr shaped him from a pig-skin cast into the fire – in the same working as Odin’s ring Draupnir and Thor’s hammer. His golden bristles light the darkest night, and he draws Freyr’s chariot or carries the god himself.
When the gods bury the dead Baldr, Freyr rides Gullinbursti to the pyre – an image of shining grief. The golden boar is thus an emblem of the sun, of fertility and of the wealth the Vanir embody.
The boar was holy to the Norse – and above all to the Vanir, the gods of fertility. At the Yule feast the sonargöltr, the „atonement boar", was led forth: hands were laid on its bristles and solemn oaths sworn. Freyja too rides a boar, Hildisvíni. So Gullinbursti is more than a shining mount – he is an emblem of the sun, of growth and of the power that returns in spring.
And the cult is tangible in archaeology: the Anglo-Saxon boar-helmets of Sutton Hoo and Benty Grange bore a boar as their crest – a protective symbol in battle. Whoever has the golden boar engraved carries on one of the oldest sacred animal-forms of the North.
Freyr · Sindri & Brokkr · Treasures of the gods · Draupnir.
Snorri Sturluson, Skáldskaparmál (35), Gylfaginning (49). Rudolf Simek, Dictionary of Northern Mythology.