Grand Broken Circle Artifact has restrictions on where or how it can drop.
Grand Broken Circle Artifact are currency items that can be dropped by Runic Monsters and Excavated Chests from Gwennen expedition encounters. Can also be obtained with Dannig in exchange for Grand Sun Artifact.
The naming of the artifact progression has been changed: Common → Greater, Greater → Grand, Grand → Exceptional. [Undocumented This change was not documented by any official sources. It was discovered through player testing or datamining.]