let's see here,  known facts about Pearls.
They are custom made gems used as a status symbol or ornaments for the gem hierarchy.
This makes Pearls at best a servant class or at worst a slave class.
According to what Peridot says in "back to the barn" other gems find Pearls attractive.
Pearls seem to incorporate dance movements into every day actions.
Pearls seem to all wear skin tight body suits and veils. (even rose's Pearl up until her last regeneration)
Pearls were not designed for fighting. (sworn to the sword/friend ship)
Rose's Pearl is all about Sword play but her summoned weapon is a "spear"

Question? if Pearls are not suppose to fight why dose Rose's Pearl summon a spear? unless it had a more utilitarian purpose.
 
A "spear" with a drill like blade and expandable handle (Short or wand version for close combat and the longer javelin for throwing)

Servant/slave + Attractive + dance + bodysuit/veils + a spear like pole that can screw into the ground and be expanded  = Dancing Pole

But that's just my twisted logic

first page

Spear Truth 01

Bonus picture

Orion Slave Pearl