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livewithstyle
Since: May, 2016
9th Mar, 2017 01:58:15 PM
Some googling makes me think this might be from R.A. Salvatore's Demon Wars Saga— there's a wiki page here detailing the gemstone magic in that universe, and your cat's eye example matches. https://en.wikipedia.org/wiki/Corona_(fictional_world)#Gemstone_magic
So rocks gave different powers. Cats eyes have night vision (surprise surprise) others gave enhanced strength and stuff like that. Don't remember much of the plot, one of the side characters was an aspiring friar or something like that. Don't have much else sorry