All Indian sandstone paving can be stained these stains can be more, or less, visible depending on the colour of the stone. We would always recommend sealing your stone directly after installation, cleaning up spillages immediately and keeping to a regular maintenance routine. If after a few years you find that your sandstone has become quite heavily stained, we would recommend using a heavy-duty natural stone cleaner such as New Clean 60 from Universal Sealants.
Indian sandstone as with all natural stones are susceptible to discolouration and damage from acid rain. This is an unavoidably realty of living in the modern world, but these affects will take quite some considerable time, normally many decades, to manifest themselves as damage on your patios surface. There is very little point worrying about this, as there is nothing that can be done to avoid it. We would always recommend regularly sealing and undertaking regular maintenance of your paving, to minimise these effects and to keep it looking good for as long as possible