Geode Dragons are closely related to Stone dragons. They are covered in a hard stone-like material as well as beautiful crystal. Their wings are entirely useless for flight, but they help attract mates. The dragons with the most brilliant and colorful crystals are more likely to mate.

Dragons are highly-intelligent reptilian creatures that—from a human perspective, at least—appear to live forever. Many different varieties of dragon exist, each with their own unique qualities, habitats, and behavior. Adolescence in dragons is usually marked by the growth of a hatchling’s wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. In Galsreim, dragons and humans coexist peacefully.

Diamond is a sacred dragon, beloved by his weyr, which is a group of dragons. The only dragon who accompanied Starbit on her egg-hunt was Phantom, who swears blind the egg was found in a nest of sparkling crystals and glowed like the moon. Thusly, he has been praised and adored since he was a hatchling, and has grown up vain and proud.

He is deeply in love with Tiffany, but she is one of the few dragons, if the only, that does not respect him. She dislikes his "dirty genes" as she calls them and refuses to be his mate. Many arguments have risen in the weyr due to her behavior.

His name comes from a song title.