I would absolutely push for a replacement. Granite is far too pricey to live with a crack like that, especially in an area as visible as the front of the sink. Did it crack during installation, or was it already cracked before they installed it?

Customer satisfaction goes a long way with reputable contractors. Was this project with a contractor, or direct with the granite supplier? The Contractor will be inclined to side with his client!

Replacement, my clients would never except that.

Thank you all for your comments and advice. We purchased directly from a local fabricator with a great reputation, we are hoping for resolution.

I would have someone who knows granite and is not in any way connected with you or the installer to inspect it and give you their honest opinion. Arm yourself with knowledge and then fight if you have to.

Being a granite fabricator I can tell you, we have run into situations like this. Were you aware of the crack before they installed it and their resolution was the rebar supports, or was this something noticed after? Fissures are inherent in natural stone, and as long as they are not structural, repair is suitable, however, in the end, we always want our customers to be happy. When the customer requests replacement after other solutions have been exhausted, we grant our customers wishes. If this fabricator is licensed (hopefully for your sake) then you should be able to contact the Registrar of Contractors (or applicable state licensing board) and have them investigate for you to come up with a resolution. The worst case scenario, if the contractor will not comply, is that a bond goes against them so you can pay someone else to fix it.

Metal rods are used at the area in front of the sink so that the countertop doesn't crack during transit and installation. Fissures are common in some stones, does the "crack" stop or go all the way to the edge of the countertop? If is stops it wasn't broken off and glued back on.