I have a new countertop(3 weeks old) . At the install I showed the installer what apperaed to be a crack. The sales peson claims it is not a crack but a fissure. The surface is rough and they put filler to make the area smoother. Can a fissure be rough like a crack and need to be filled or am I being mislead? There are fissures in other area that are smooth to the touch. Thanks