Jelly opal is an opal that has a jelly look to it. It is just like crystal opal but the opal color is a little bit faint so you can see through the opal pretty easily. ... The nature of jelly opal means that its appearance is usually due to its relative thickness. Four golden brown Citrines and four, 3 mm. pearls surround this gem. A white Mabe' pearl pulls the eye down to its cushion shape below the ensemble.