If you have an extra piece of the counter top material you can use this.
Repair cracked granite hearth.
Again i d suggest contacting a good mason who understands fireplaces and foundations.
Fissures are lines formed in the pattern of the stone by the borders of various crystalline groups within the stone.
I work for a granite company never recommend marble as a hearth stone.
Granite countertops are relatively easy to take care of and such preventive maintenance as cleaning up spills quickly and avoiding setting hot pots on them will keep the surface in good repair.
You can also remove a bit of granite dust from an area that is not visible such as the underside of a counter top.
Properly installed granite countertops are not likely to crack but if they do there are steps you can take to repair them.
Fissure any discussion of cracks in granite countertops must also include an explanation of fissures.
Caulk is not a safe repair for hearth settlement.
Learn from expert kevin ressler how you can quickly and easily fix most holes cracks or chips in you natural stone tiles counters floors and walls using.
Repair may be a moderately difficult thing since you really need to eliminate the underlying problem.
I have even incoprorated glitter and crushed or chipped precious gems mixed in resin to fill cracks to make it look like a vein of precious drusy stone thus making it a unique stone inclusion.
Best granite marble quartz repair ever with instantbond super glue adhesive how t.
Connie phillips above has the best idea i have seen so far.
Long or full thickness cracks and or areas with multiple cracks likely need repair.
The crack will just reappear.