<p>We all know the Diamonds started production of all other gem types to serve them, but who made them?
</p><p>I have three theories:
</p><p>-The Diamonds are creations of another alien race themselves before they revolted.
</p><p>-Like the Titans in greek mythology they were born from the (sentient) homeworld. Before overthrowing their "mother" and taking her over.
</p><p>-They naturally evolved or "formed" like the autobots and decepticons did on cybertron in Transformers.
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<p>To be able keep the gems stable, the creator of the gem race made the diamonds to have a helping hand in organizing them, but the Diamonds betrayed and killed off their makers and turned Homeworld to what it is now today.
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<p>In off color (I believe) the hole in the wall in which the robot things were sent through (the hole was later blocked) was gem-hole shaped, but bigger and had markings above it. I think that may have something to do with the creation of the diamonds.
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<p>That Transformers analogy wasn't accurate at all, the Cybertronians were created by the sentient core of Cybertron. At least The Primes were, which served a role similar to the Diamonds. You really only listed your 2nd theory twice. Personally I'm a fan of the Sneoples created them theory, although it also would be really cool if there was a 5th Diamond.
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<p>I have a theory i feel some ancient alien made white DIAMAND white DIAMAND finding it hard to rule alone, made blue and yellow DIAMAND, who controlled the many colony’s then blue began to become lonely yellow made pink DIAMAND on one of her colony’s this is why in the new special pink DIAMAND was acting like yellow was her mom because she sorta is, this is also why blue seemed to be the only one TRUELY really affected by the shattering of pink
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So i have idea that the ancient species called genesions accidently created diamonds and gave them sapience so like how galvanic mechamorphs were created