QUESTIONMy fabricator is saying the crack in my countertop is a fissure. It looks like a crack. What is a fissure and is it a defect?
ANSWERANSWER - The term "fissure" is used commercially in the stone industry to describe a visible separation along intercrystalline boundaries of a natural stone. This separation may start and stop within the field of the stone or extend through an edge. A fissure differs from a crack in that it is a naturally occurring feature in the stone that may be found in other areas of the same slab or other slabs of the same material.
With marble there are classification Groups A, B, C and D. Groups C and D marbles commonly have lines of separations or fissures. Group C is the largest and most colorful group of marbles, that also contains significant holes, voids, lines of separation and structural flaws. It is normal to repair these groups of marble during the fabrication process will fillers.
Generally speaking, cracks can be felt by running your finger over it, but a fissure that has been properly filled and polished will not be felt.