It should be, but make sure you clean and fully dry the surface you want to glue it together. Mine worked but only for a couple of weeks.

If applied carefully, none of the products is visible from the top. So we can’t say what it would look like if applied to the top's surface, but we can’t envision why it would be on the surface.

We, as Akfixstore, have not used this product in relation to hot items. However, if the hot things were not going on the marble directly from the oven (baking pan), there may be no adverse reactions. We have two marble statues that were repaired and sit on a mantle in front of a gas fireplace used during the winter (3-4yrs), and they remain intact. We are assuming that the pastry board will remain stationary during use.

Yes. Please follow the instructions on the product to get the best result. It is a fast setup and strong. 

You need to cut off the tip with a utility knife before using it. Then, you can reuse it several times over the month, and it will continue to flow. 

The liquid is a few oz, and the spray activator lasts depending on how heavy you spray it. Approximately, it might go for 25+ feet.

Yes, the product will work for stone outdoors. It is a very fast setup and very strong.

It works great, even in Arizona heat.

The product is capable of joining the marble project, and it will work on quartz too. Please remember that the glue sets in seconds; there is no room for adjustment.

If your project consists of new stone pieces, just follow the product's directions. If you are 're-sticking' the stone pieces together, you will benefit from roughing up both surfaces with 1000 grit sandpaper first, then cleaning with alcohol. 

Sure, it should work for this application. Just be sure not to torque the glued surfaces.