Granite is a crystalline structure so it will always have tiny pits or spaces between the various mineral crystals. You usually do not see them on a larger piece because they are so small and the overall appearance is polished and mirror like. Some types of granite can have natural fissures which may look like cracks. These are not structural defects but are naturally occurring markings resulting from the immense heat and pressure that formed the granite. These characteristics are part of the natural beauty of granite and have no impact on the function or durability of the material. Natural products vary and can not be expected to look completely uniform or manmade.