Different granites have different resistance to stains and scratches. You can ask the designer or supplier about the characteristics of your granite products. Although putting something directly on the granite will not affect the main body of the granite, it is still recommended that you use a cutting board to prevent the knife from becoming dull. Repeated cutting with a knife in the same place on the granite countertop will wear the polished surface.
Light-colored granite is easier to color than dark-colored granite. Immediately removing spills will help avoid staining. To prevent staining, the granite should be sealed before installation. According to the sealing condition, we recommend that you reseal it regularly. Coffee, red wine, edible oil, butter, lemon juice, tomatoes and other acidic substances sprinkled on the stone surface should be removed as soon as possible. Use appropriate cleaning agents, which are based on ammonia, and will corrode granite. China Stone Network
It is not necessarily true that a thermos bottle will not burn directly on top of the granite. If you put the thermos bottle directly on the granite surface, you have to be careful after removing it, because the stone will absorb the heat of the bottle, making you unable to touch it.
Advice: Some polished stones, including some granites, are filled with resin before leaving the factory. The purpose is to fill the gaps and potholes of the stone to improve the beauty of the stone. The thermos will destroy the epoxy and cannot be recovered. This may be difficult for you to judge, you can consult an expert. Do not put the thermos directly on the resin countertop.