Annika's locket

Annika's locket is a junk item in Fallout 4.

Characteristics
This item does not appear to have any use aside from junking for 2x silver, or selling. A quest item obtained pop-up occurs after picking up on PC, but it is not marked as a quest item in inventory.

Location
Chestnut Hillock Reservoir (near the bottom of the lake, next to the non-interactive skeleton of Edwin)