Well i was gonna suggest the opposite. Remove the crack's 3D work and just paint a crack on with some black/normal map.
If no one gets close enough to see it what's the point in having that much detail.
Maybe just have a notch in the rim at the top where it's more visually obvious/directly affects the siluette of the model, then use a black illustrative fork lighting-ish line work representing the continuation of the crack through the pot.