Q. I've heard some people say that all stone should be sealed. Others say this isn't the case. How do I know if I should seal my countertop?

A. This is a tricky question. Why? Because not all stone was created equal. Add to that the fact that many stones that previously needed to be sealed have now been treated in the processing of the stone and no longer require it. The best way to answer the question is determine if your stone should be sealed is to use the lemon and oil test developed by renowned stone restoration expert, Maurizio Bertoli, before you purchase your counter. However, if it is already installed, no worries! Just pour water on your stone, wait 30 minutes, and wipe it away. If the stone darkens, it needs to be sealed. If it shows no signs of darkening when wet, it does not need to be sealed. Check https://surphaces.com/testing-stone-for-kitchen-countertop-usability-the-lemon-juice-and-oil-test/ for additional information.