I'm working on reviving an old bathroom, and one of the jobs is to spruce up the floor, which is the original and beautiful hex tile. From the pictures, you can see that some of them are still reasonably white, but there are others that have developed at yellow-ish tint. Interestingly, the discoloration seems to be happening on the whole tile rather than a general area that was either more trafficked or damp. The picture with the particularly yellowing/brown tiles is under where the toilet was, which may provide some insight into where the stains are coming from.
I'm trying to remove these stains! Some of the ideas I have run across online are: hydrogen peroxide, baking soda and vinegar, stone poultice, wet/dry sandpaper. What suggestions do you have?