Here's what I got from plugging 'Alpine Fractal SH' to fake stones' surface shader node. :o Don't know why, but these egg-like thingies creep me out somewhat. Might do something fun with them in the future.
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The Alpine fractal at default creates large feature scale shapes with large displacements.
Displacing your relatively tiny 1 metre sized stones with this massive fractals causes them to explode and do all kind of weird stuff.