Soul diamond

Soul Diamonds was the name give to diamonds created from the ashes of deceased Corellians as part of a cultural tradition. When a native of the planet Corellia passed away, their bodies would be cremated and then their family would have the ashes compressed into a diamond. These pure synthetic diamonds were blue-white in color and sometimes gave off a subtle glow from within, with many believing that a part of the deceased's soul remained in the crystal. Many families incorporated their ancestor's Soul Diamonds into jewelry or mounted them in displays which used repulsorlifts to keep the gems floating in mid-air. The mounted Soul Diamonds of one family would often be displayed together.

Behind the scenes
Souls Diamonds were first mentioned in Suns of Fortune, a sourcebook released in 2014 for Fantasy Flight Games Star Wars: Edge of the Empire roleplaying system.