Granite Slab Countertop Fissure question


Granite Slab Countertop Fissure question? The pictures attached are from a new install and we have been told by the installers that this is called a fisher. The granite is Bianco Antico.

Any feedback for us would be greatly appreciated. To us it looks as if it is cracked, but we are not expert and would like to see if you would have any thoughts on it.


ANSWER - The photos clearly show that the vein separation is a fissure, which naturally occurs in some stones.

By definition of the American Geological Institute a fissure is an extensive crack, break, or fracture in the rock, which may contain mineral bearing material.

I can see that they have the back of the slab stabilized with a fiberglass mesh bonded to it.

The crack looks open.  You should not be able to feel it if you run your hand across it.   The Marble Institute of America says that a repair of the stone is permitted when the repaired region is not in a structurally significant area of the countertop, and when it can be accomplished skillfully so that the repair is consistent in color and texture with unrepaired regions of the slab.

4 thoughts on “Granite Slab Countertop Fissure question

  1. Doug Needham says:

    Hi Donato, I’m a building contractor in florida. I built a spec house and sold it with granite tops. After 8 months the buyer is complaining about fissures and a possible crack. The granite looks the same as when installed. The company I hired said all fissures. But I have my doubts on one and would like your professional opinion. I have pictures that I can send as well. I appreciate a response as I want to take care of this as soon as possible. He calls alot. Thank you

    • Donato Pompo says:

      Fissures are commercially described as a visible separation along intercrystalline boundaries. 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.

      A crack is in a stone is the result of manmade mechanically induced stresses during handling, fabrication, transportation, or installation.

      You can’t determine whether you have a crack or a fissure from photos. Although normally a fissure is a crystalline inclusion, rather than a separation within the granite material itself.

  2. Douglas Needham says:

    thank you donato, if its a crack thats been filled, is the granite company liable to replace it at theyre cost. i paid for level 3 and another granite compant says its a crack and they wouldnt have installed it and looks like seconds?

    • Donato Pompo says:

      According to NSI Dimension Stone Design Manual 16.2 Cracks in the Countertop section:
      Cracks that occur as a result of handling-induced stresses are often more difficult to repair, as they commonly include chipping in addition to the crack. Repair is frequently performed by injection of a penetrating resin adhesive, which maybe be dyed to match the stone, and then rebuffing the area after curing of the resin. In many cases, the entire stone must be repolished to make the repair unnoticeable. If the repair is attempted but unsuccessful, the stone is to be replaced with a new piece.

Leave a Reply

Your email address will not be published. Required fields are marked *