For many different reasons, marble may become cracked. Replacing marble of any size is very expensive, so repairing it yourself is a great alternative. Using a precise mix of marble dust and polyester resin, you can have your marble slab looking like new again.
Put on your safety gear, and use the soft-bristle brush to gently remove loose pieces of marble from the crack. Wet the area and allow it to stay wet for better bonding between the existing marble and the epoxy adhesive.
Place a small amount of epoxy adhesive around the inside of the crack.
Measure 113gr each of powdered marble, also known as marble dust, and polyester resin or calcined magnesite. Pour the elements into the bucket and stir with a wooden spoon. The consistency should be pasty but not too thick or watery.
Scoop a small amount of the mixture onto the putty knife, and place it inside the crack. If it is a thin, hairline crack, use the tip of the putty knife to push the mix down into the crack. Overfill it so there is marble mix above the surface.
Smooth over it with a trowel, and use the side of the trowel to gently scoop off the excess marble. The filled crack should now be flush and even with the top surface. Allow the repair to dry for 24 hours.