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(Mistborn Era 2 Spoilers )
Also, I'm under the impression that the type of spren is only one of many factors, and metals, shape, and type of gemstones are more important. It feels like it also might be used with some gyroscope-esque device and something similar to the way spanreeds work, with the rubies.
curious, did you hear this somewhere, or just an idea that popped into your head?