Thank you for your question. The slate is not sealed. This couple did not want that look. They wanted a more lived-in atmosphere. Now, leaving natural stone unsealed is not for everyone or every situation. In fact most situations should probably consider sealing natural stone, but this particular situation was an exception. We used Minnesota Tile ( https://www.houzz.com/pro/lynn-chock/minnesota-tile-stone) as a supplier for this product.