Go to the Hanged Man and speak to Isabela. Hawke will give the necklace to Isabela, who explains that the necklace is a Rivaini fertility necklace that is meant to increase fertility and bring about love.
Note: Even if you have romanced Isabela fully and she claims she has fallen for you, she still acts hesitant about love, saying that she'd rather stick with lust.
Only tested on ps3pc console.
Rewards EditRivaini Fertility Talisman
+2 health regeneration rate
+2 mana/stamina regeneration rate, which Isabela will equip as an amulet