Green Jewel

Green Jewel is a female background Earth pony who appears in A Friend in Deed, Magical Mystery Cure, and Pinkie Pride. She has a lime green coat, deep sea green mane, orange eyes, and a cutie mark of two diamonds. She is unnamed in the show, but she is named in merchandise and other depictions.

Design
Green Jewel shares her design with "Chilly Puddle", "Purple Haze", "Welly", and S05E24 Unnamed Earth Mare #3 and her mane style with Sassaflash, "Parasol", Prim Posy, "Drizzle", "Graceful Falls", "Downdraft", and Honey Rays.

Depiction in the series
In season two, Green Jewel briefly appears during the Smile Song in A Friend in Deed, with her eyes closed. In season three, she appears in Magical Mystery Cure during Morning in Ponyville, with her eyes open, and during A True, True Friend. In season four, she appears in Pinkie Pride during the Cheese Confesses flashback, once again with her eyes closed.

Other depictions
Green Jewel is a playable character in Gameloft's mobile game, added in the version 2.6 update on December 14, 2015. Her in-game description states, "With dual diamonds as her Cutie Mark and hair that's blue -- there's no doubt in our minds that Green Jewel's the pony for you!"

Merchandise
Green Jewel is named with a trademark symbol in the ninth and tenth waves of mini-figure toys and collector cards. According to both collector cards, Green Jewel "makes everypony smile when she smiles!"