Hi everyone, I have read through many questions regarding sealing marble backsplash. We had our quartz countertops installed a couple weeks ago and will be installing the marble backsplash next weekend. Attached is a photo of the backsplash we purchased (Carrara Rhomboid Bianco Polished Long Octagon Black Dot). I have read quite a bit about sealing it before grouting, which is what we plan to do (grouting with unsanded white grout; silicone at base between countertop and backsplash). I suppose my question is more product related, as I have read some accounts of the sealant discoloring the marble, which would be disastrous for me as I spent a lot of time finding a quartz with the same undertones, as well as everything is coordinated so that the background hue of marble is just right. I do have a sample piece that I plan to test the sealant we purchase on before application, but I really don't want to purchase multiple sealants if at all possible. Can anyone suggest the best sealant for polished Carrara that will not cause discoloration? Thank you so much!