Cat Eye (The gemstone) how to ?

I’m trying to replicate this effect :
But to no avail for now.

I’ve tried bump offset and it’s working but it’s giving me horrible rippling effects:

I’ve tried mat-caps as well but the cat eye effect only goes in one direction.

At the moment I’m trying to create the effect with vectors but it hasn’t clicked yet.

Does anyone have any suggestions/tips on how to tackle this task ?

It looks like it’s behaving like a Clear Coat material with a a anisotropic material underneath. There’s some threads and discussions about how to make a anisotropic material in UE4, but there’s no easy built in solution.