Rose's shield, sword, and even her flag have a pink triangle in the very middle. Triangles have been used in the series to represent the Diamond Authority. This sign also differentiates with her gem so it could prove that at one time she was a part of the Diamond Authority. In the episode "The Return" Jasper notices Steven's shield she says," that shield,that symbol!" Proving that she knows the pink triangle shown.
Steven Universe Theories
By -Endless_Oasis-
Just different theories about Steven Universe that I have came across and added my own thoughts to. WARNING:... More