The Scrimshaw, Mûmak Tusk artifact can be found at Fern Outskirts, in the southern part of Sea of Núrnen.
Scrimshaw, Third Age, circa 2940
This carved tusk commemorates the conclusion of an epic hunt. Here we see two Dwarves: the first is wielding a mighty axe and striking a deadly blow against a giant Mumak. The other, who appears to be his twin, flees from the beast in a panic. The quality of the workmanship indicates that the artist was a master craftsman under the influence of strong ale.
"There, it's finished… a true masterwork. What a fine carving. The front, I etched us killing this here Mûmak. And the back… our next prize, The Mighty Graug! A beast like that is a hunter's legacy.
Show me the carving…
Isn't it magnificent? Such detail! Look at me striking the mighty beast. Blood everywhere.
And why am I etched running away from the Mûmak in terror?
Artistic license, brother Torvin! If you want to be the hero, I suggest next time you make the carving!"