yes it can be stained with oil-based minwax. Because oil-based minwax provides long lasting work.It penetates deep into the area and closes the grouts. This oil-based minwax is ideal for all wood items and also wooden floorings. Two or more colours can be mixed together to get the required colour to fill the grouts.
Yes, you can stain your grout with oil-based Minwax, assuming you haven't sealed your grout already. After staining, I would recommend sealing, because I am not sure how long the color would last without it.
