There are a few farmhouse sinks that have a self rimming flange.

What would be more feasible is to install a new sink that has a flange, or rim (some called self- rimming), as that would easily cover a cut in the countertop. Corian can be refinished in the field, so maybe a fabricator could add finished material around the sink cut, but I'm not sure. Given that A) modifying a countertop in place so that you have an exposed finished cut is extremely difficult, and B) corian is not solid all the way through (it has a particleboard core), I would say this idea is only somewhat feasible. Basically, the edge of the countertop at the sink would either be exposed, or it would finish tightly butting against the side of the sink if you use a sink style that raises up higher than the countertop. If you search images online of farmhouse sinks, you will find that many of them install below the countertop. Opening larger cans of worms is also a concern.Great question about the sink. This house might go up for sale, and cleaning everything up to make it look nice on the cheap provides a far better return on investment than throwing brand new stuff at it that will rarely provide a return. Doing a little epoxy caulking, maybe creating a tiny crevice to insert a smooth line of epoxy would be ok. So tearing into a second one is a terrible idea. I’ve got another bathroom I still need to get built. If I understood what is the ideal epoxy to really BOND corian, then maybe I could solve both these Corian issues… cheaply. But it’s only a matter of time before the mold gets in behind it, and it all needs to be peeled out again. I’ve also got the areas in the corian shower that look great after peeling out the old silicone (or other) caulk and running a fresh bead of silicone caulk. Will it perhaps “melt” the corian a little sort of like PVC primer and glue do? Or am I just bonding it with epoxy? If there’s one question I have to ask, it is… Can you cheap out and achieve a short term or long term solution to this kind of problem? People will be able to learn from my experience.

This will document whether cheating out is worth it or not. I agree that if we are going to talk about grinding out the crack to any significant degree, then replacing everything becomes the next step.

Corian sink cracks