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Size distribution of fragments post-exposure measured by serial sieving of fragments. The left 4 groups show the size distribution of fragments for natural stones treated with 170 kHz bursts, while the right 3 groups show the size distribution of artificial stones treated with 170 kHz, 285 kHz, and 800 kHz bursts. All measurements are mean values for stones treated in each category. COM = calcium oxalate monohydrate.
