silver pendant, three-cornered hat of Odin or horn triskell

This symbol belongs to Odin, represents three drinking horns intertwined, it is also called Horned triskele
It 'a symbol that represents the loyalty all'Asatru (Icelandic word meaning "Loyalty to the Gods"),
The origin of this symbol can also be found within this Nordic myth CEH Kvasir sees as protagonist and the three horns in which his dangue was collected.

In Nordic mythology, Kvasir was the wisest of the Vanir, generated from the saliva of all the gods. Two brothers, the dwarves Fjalar and Galar, invited him to a party in their gloomy cave and killed him. The dwarves mixed his blood with honey and preserved it in a cauldron for two years. The fermented mixture giving rise to the cider of poetry, which was held in three Son horns, and Bodhn Odherir - "what excites the spirit" - were the names that gave the grim contenitori.Coloro who drink it become inspired poets. Some time later, the two brothers killed the giant Gilling and his wife. The son of Gilling, Suttung, he went to find his parents and threatened the dwarfs would have killed them. The two brothers cider delivered to Suttung because it would spare their lives. Suttung hid it in the center of a mountain and ordered the Gunnlod daughter watch him. Suttung boasted of his treasure, and when the god Odin learned of went to Jotunheim to take over the cider. Disguised as a peasant, Odin worked all summer to his brother Suttung, Baugi. A work done, Odin asked Baugi giving him a drink of cider. Baugi, reluctantly, he made a small hole on the side of the mountain and into the room where the cider was preserved. Odin turned into a serpent and crawled through the hole up to enter the hall where Gunnlod watched cider. Taking up the appearance of a giant, Gunnlod persuaded to give him three sips of cider. Odin took all three vessels, turned into an eagle and flew back to Asgard. According to the book by Kevin Crossley and Holland, "The Norse Myths" (p. 191), the Kvasir name is derived from the Russian word "kvas", which indicates a type of fermented beverage similar to beer, but stronger.