Simply slapping some mortar on the crack will not solve a thing even if you bother to find some heat resistant mortar.
Repair cracked granite hearth.
Properly installed granite countertops are not likely to crack but if they do there are steps you can take to repair them.
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.
Long or full thickness cracks and or areas with multiple cracks likely need repair.
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.
If you have an extra piece of the counter top material you can use this.
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.
You will need no more than 2 teaspoons of granite powder to repair most cracks under 1 foot 0 30 m long.
Caulk is not a safe repair for hearth settlement.
Fissure any discussion of cracks in granite countertops must also include an explanation of fissures.
Connie phillips above has the best idea i have seen so far.
You can also remove a bit of granite dust from an area that is not visible such as the underside of a counter top.
In an easy to spot case of movement and separation between a fireplace hearth and the building floor take a look at the white caulk installed in an open crack between the hearth face and the floor in our photo left.
Again i d suggest contacting a good mason who understands fireplaces and foundations.
Best granite marble quartz repair ever with instantbond super glue adhesive how t.