Crystal resonator

Crystal resonators were devices which could be used to detect unnaturally high concentrations of gems or crystals. Following the devastation of the moon Jedha by the Galactic Empire's Death Star superweapon in the year 1 BBY Imperial forces dropped crystal resonators onto the moon's surface to look for kyber crystals. The resonators detected an unnaturally high concentration in what had once been the Catacombs of Cadera. When Queen Trios of the planet Shu-Torun—who was advising the Empire on mining kyber crystals and supplying them with miners and equipment—saw the reports, she confronted Imperial Commander Kanchar and demanded to know what he knew about the crystals in the catacombs. Kanchar revealed that they were the crystals that had previously been stolen by Saw Gerrera, leader of the rebellious Partisans.

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