Diamonds are the only Gems that can reproduce as Gems, and to date the only ones that have reproduced at all. Diamond Essence, extracted via contact with water, not only heals physically damaged or mentally Corrupted Gems but is also what is injected into a planet to breed.
Lapis Lazulis prepare the landscape for Kindergartens and Peridots manage/maintain them, making both the drones of Gems. Plus, hexagonal cells are a recurring visual motif with Homeworld.
Amusingly while White, Yellow, and Blue behave like queen bees, Pink was treated more like queen ants which makes the size difference kind of funny if it was intentional.
If you think of them as “solar powered robots” who have to discover and learn their own free will, the metaphor becomes more than just amusing.