Ruth's Engagement Ring

"True love follows this ring wherever it goes, my son...Take it, and I'll know, even if I never see you again, I'll know you'll find love. I'll know you'll be happy."

- Ruth to her son

The Green Peridot Ring is a magical item featured on ABC's Once Upon a Time. It first appears in the third episode of the first season.

History
David, a shepherd boy on a farm, assumes the role of prince due to his twin brother having been adopted by King George years ago and dying at the hands of Behemoth during a sparring match. He takes on the name Prince Charming. The mission his twin brother was supposed to have undertaken was to defeat a great dragon. Prince Charming must tackle the mission now that he has taken his brother's place. Upon the successful slaying of the dragon, King Midas, who was both impressed by Charming and wished to join his kingdom with King George's, gives his daughter, Princess Abigail to him in marriage. Now he has no choice but to assume the role of prince and cannot go back to his mother, Ruth, so she gives him her engagement ring as a parting marriage gift.
 * -|Before the Curse=

The ring is then placed in a jewelry box for safekeeping and taken along in Princess Abigail's carriage when Prince Charming and Abigail set out for their engagement party. A fallen tree blocks their way, which was actually a trap set up by a vagabond Snow White. While Prince Charming and his men are busy trying to figure out how to move the obstruction, Snow reaches into the carriage, grabs the jewelry box and takes off on horseback to flee. She outruns Prince Charming even after he catches up with her, and later sells the ring to the trolls who reside on the Troll Bridge. Prince Charming manages to ensnare Snow in a net, and forces her to help him get back his ring or else he will turn her over to the Evil Queen, who wants her dead for murder and treason. During the ordeal, Snow once again tries to outsmart Prince Charming by tricking and running away from him, but instead she faces danger when the Evil Queen's Black Knight captures her. Prince Charming saves her by killing all of the black knights. They continue onto the Troll Bridge, where they meet the Troll group. The trolls are very unhappy that Snow is asking for the jewels in the box back, but also that she brought a stranger with her. After sifting through Prince Charming's belongings, they find the wanted poster of Snow, and conclude they would receive more in rewards if they turned her in. Prince Charming tries to distract them while Snow prepares to run but the trolls grab Prince Charming, so Snow resorts to using the Fairy Dust she has been carrying around, in which the dust transforms the powerful enemies into harmless insects. Having gotten Prince Charming's jewels, including the ring back, they set out to part ways soon after. Snow tries on the ring jokingly, and says it isn't her style.

When Prince Charming breaks free of the Evil Queen's castle with the help of the Huntsman he comes upon Rumplestiltskin. Rumplestiltskin takes the ring and magically enchants it so the closer he is to Snow's presence, the brighter the ring's gem glows. He will not give it back to him without a price, which causes a brief sword fight between the two though. After Prince Charming agrees to a deal of hiding Rumplestiltskin's true love potion in a beast and succeeds, he sets off to find Snow using the ring. It guides him to her, and with true love's kiss, he awakens her from the sleeping curse.

The ring becomes one of Snow White's possessions that stayed with her until the very end when the Dark Curse was enacted. Thus, Mary Margaret still has the ring in Storybrooke.
 * -|During the Curse=

After the Dark Curse is broken, Mary Margaret continues to wear the ring.
 * -|After Broken Curse=

Reawakened: A Once Upon a Time Tale

 * Mary Margaret wears the ring as a necklace.