"I just noticed something about our 1960s house that we moved into. I'm obviously keeping all of these amazing vintage features, the original, but I noticed that the shine on this tile doesn't seem quite right when the light hits it. We've been here for like a month and a half and I'm just now noticing this, so I want to find out if they painted it. In part I'm suspicious as well because the shower upstairs has the matching tile to the tub. So I want to do this in a bit of an inconspicuous spot just in case I'm wrong, but let's see. Okay whatever this stuff is is really, sorry, is really strong so I'm gonna try maybe a little bit of sandpaper. Let's see if this works. I might need two hands though first to test it. Okay I've been rubbing at this for several minutes with the sandpaper and it's really not doing anything, but that looks weird too. Not like I would assume a tile would look like if you were sanding it, so maybe I need to use like a chemical stripper just like in a test spot. What do you guys think? I covered this well in my pajamas, so yeah I'm open to suggestions and I'll definitely come back to it because this would be super cool if it is blue."