Buy Dwarven artifact

It is a miscellaneous quest received from Courier in any city.

Walkthrough
After buying a dwarven item, a courier may deliver a Letter from Calcemo to the Dragonborn who is next visiting a town or a city. The letter asks to bring the item to Calcelmo; he will pay dearly for it.

Go to Understone Keep and meet Calcelmo, sell him the requested artifact for twice the item's base value. If the Dragonborn has Speech skill at the level 50 or higher, he may persuade or intimidate Calcelmo for two and a half times the item's base value.

Trivia

 * At the Skyrim official guide this quest is marked as World Interactions: Items of Interest.

Bugs

 * Calcelmo may not acknowledge that an item is in your inventory.
 * Fix:Removing the item and getting it back again, such as dropping it and picking it up or trading it to a follower temporarily, may fix this.
 * If you have sold/lost the item, you can add it to your inventory through the console commands and it may be accepted by Calcelmo.