Onyx

Onyx is a defective pearl that came out too early and thus became a clay-like substance that shapeshifted into a quartz.

When serving Homeworld ONLY
Onyx as a full on homeworld gem wore a grey v-neck shaped sleeveless top with a white diamond insignia. She often wore her hair up the way white diamond's pearl did but she wore it down because she didnt like it

When sided with the crystal gems
Onyx wore a purple top and skirt with a massive star in the middle of it the shirt in question was a halter-top (like the one CG pearl wears) with a white star insignia in the middle (implying she may have had still some loyalty towards Homeworld).

After the events of "Made of Honor"
Onyx now is loyal to both sides equally after finding out that the one that she had betrayed homeworld to join (Rose Quartz) was actually Pink Diamond. She wore a purple V neck halter top with a white-diamond insignia and a Purple sash shaped like a star.

Abilities
Onyx had standard shape-shifting abilites those including: Shapeshifting, Bubbling and fusion.

Homeworld:
Onyx was loyal to her diamond White diamond Homeworld was overprotective of her and made sure she stayed on Homeworld and they loved her .However when she joined the crystal gems in the rebellion they censored her name and anything to do with her in Era 2. The only gems who know about her are as follows
 * The Great Diamond Authority (Pink included) (Yellow diamond was the one who officially censored anything to do with her)
 * Gold diamond
 * The crystal gems
 * Bismuth (the one who shattered her in the CG's)

Crystal gems:
The crystal gems didn't like her at first but welcomed her when she joined and they loved her and they hid her from bismuth because they didnt want bismuth to know about onyx and then bismuth caught a glimpse of her and shattered her because she thought she was a homeworld gem. She was immediately furious and they hated her.