Lovely aluminum and composite brushed copper look tile. Lightweight and very attractive. It just took a really long time to get here and I ended up having to select something else locally to put in my kitchen area. Will use elsewhere in the house. No grout is needed for these tiles but during kitchen use,especially around a cook top, grease or other stuff could run inbetween the very small spaces between the tiles that you cant clean out. Over time that would be kind of gross and probably smell to some degree. I would recommend some sort of grout,silicone or other filler for that reason. I dont know what could be used but I would be inclined to find something for that situation.  Over all really nice self stick mosaic tile, just bear in mind delivery takes a while.