• Granite is a natural stone prone to fissures, pits and weak spots.granite image by Roman Sigaev from Fotolia.com
  
  Granite is one of the hardest surfaces known to man. Made of quartz, feldspar and silica, it is used on tabletops and counters regularly. While granite is extremely hard and durable, it is also a natural stone product. This means it may contain weak spots or fissures and can crack for a variety of reasons.
  
  

Natural Fissure

• As granite was forming from molten lava, the rapidly cooling materials it contained caused some sections to shrink or form weak spots. These are known as fissures, and they can affect any granite or stone product. The polishing process of finishing a granite slab may disguise the fissure, by causing light to bounce off it. This unseen fissure could then crack under natural use or pressure on a table.
  
  

Inadequate Support

• Granite slabs are heavy, large materials that must be supported and stored properly. If the table top does not have adequate support from all angles, a weak spot in the stone or a particularly stressed area of the stone may crack. Likewise, if an area has been cut away to install a heating element, and the surrounding stone is too thin, the granite can crack from an inability to bear its own weight.
  
  

Manufacturing Defect

• Granite slabs are cut, edged, and polished before they are sold. Fissures can be filled with epoxy and masked prior to shipping or during installation. If a saw blade has caught a fissure, or if a repair was badly made, the granite tabletop could crack through normal use and wear and tear.