<p>To the best of my knowledge the only method other than Kindergartens hinted at was that Pearls were created at the Reef, and are fully customizable to their owners specifications. We know there is a Kyanite colony and we know there are Kindergartens in Homeworld, so I presume different worlds produce minerals and conditions to make specific types of Gems, which would explain why Earth’s Kindergartens predominantly created Quartzes. We also know Pearls are seen as lesser status than even the lowest caste gems. Perhaps their different method of creation at the Reef is a factor in that.
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