Quote Originally Posted by Bright-Flower View Post
I don't think anyone consciously carves things into them, more it's a metaphor for the stones absorbing the memories/experiences over time passively.
To be pedantic, the soul crystals are "carefully cut" before use to better facilitate the "capture" of the holder's memories and experiences. So soul crystals are prepared beforehand, rather than someone just picking up a random crystal in the wild and using that as a soul crystal.

Maybe it's better to think of it as a soul-facing GoPro?