Gold is called by the poets the meal of Frothi, and the origin of the term is found in this story.
Odin had a son named Skioldr who settled and reigned in the land which is now called Denmark, but was then called Gotland. Skioldr had a son named Frithleif, who reigned after him. Frithleif’s son was called Frothi, and succeeded him on the throne. At the time that the Emperor Augustus made peace over the whole world, Christ was born, but as Frothi was the most powerful of all the monarchs of the north, that peace, wherever the Danish language was spoken, was imputed to him, and the Northmen called it Frothi’s peace.
At that time no man hurt another, even if he found the murderer of his father or brother, loose or bound. Theft and robbery were then unknown, insomuch that a gold armlet lay for a long time untouched in Jalangursheath.
Frothi chanced to go on a friendly visit to a certain king in Sweden, named Fiolnir, and there purchased two female slaves, called Fenia and Menia, equally distinguished for their stature and strength. In those days there were found in Denmark two quern-stones of such a size, that no one was able to move them, and these mill-stones were endued with such virtue, that the quern in grinding produced whatever the grinder wished for. The quern was called Grotti. He who presented this quern to Frothi was called Hengikioptr (hanging-chops). King Frothi caused these slaves to be brought to the quern, and ordered them to grind gold, peace, and prosperity for Frothi. The king allowed them no longer rest or sleep than while the cuckoo was silent or a verse could be recited. Then they are said to have sung the lay called Grotta-Savngr, and before they ended their song to have ground a hostile army against Frothi, insomuch, that a certain sea-king, called Mysingr, arriving the same night, slew Frothi, taking great spoil. And so ended Frothi’s peace.
Mysingr took with him the quern, Grotti, with Fenia and Menia, and ordered them to grind salt. About midnight they asked Mysingr whether he had salt enough. On his ordering them to go on grinding, they went on a little longer till the ship sank under the weight of the salt. A whirlpool was produced, where the waves are sucked up by the mill-eye, and the waters of the sea have been salt ever since.
The Meal of Frothi – Scandinavian Folktale