If a small section of stone counter or table breaks off, you can use epoxy to permanently glue it back in place. Many kinds of stone are variegated in color, and this helps to hide the repair.

There are also clear and colored epoxies that might closely approximate the color of the stone. If small chips are missing and you can't get the repair to mate precisely, you can try using colored wax to fill the cut line after you epoxy the break.

Large pieces, or sections that have to support their own or other weight, are more difficult to glue successfully.

Professionals sometimes drill into the fractured edges and then insert metal pins to hold the pieces together and provide support. This takes skill and experience to prevent making the damage worse, so consider your experience carefully before you attempt the repair yourself.