There are many different types of sealant available and it can be a bit of a minefield choosing which one is right for you. This is not to say that all natural stone should be sealed, but there are times when it is essential. Examples of this might be if you have a north facing or particularly wet garden. Another instance when sealing is essential is if you are using porous natural stones. Be very careful about which seal you buy. Some of the cheaper seals can leave an awful looking shine on the surface of the paving, completely changing the look of the natural stone that you originally fell in love with. To avoid this sheen you need to buy an impregnating paving sealant. Impregnating paving sealants fill the holes of the stone which present moisture getting inside, while still allowing the stone to breathe.