MAPEI's Keracolor U grout is unsanded. So, it's a great choice for grouting most installations of glossy wall tile. Other good options are Ultracolor Plus FA grout and Ultracolor Plus Max grout. When grouting installations of antique or handmade wall tile, it is recommended to build a mockup (sample board) or, at the very least, test these products in an inconspicuous area before grouting.