Strange dark patches appearing

[grumpy_cake]

Hi,

I rent a property and the tiled floor in the kitchen has started to get dark patches on the tiles. I have tried washing them and they originally went away but they come back in the same places.

They appear to fade if I use a scouring pad but I am worried that I am going to damage the tile if I scrub too hard....



Any ideas?

 

[Ian]

Looks like oil. Has anything been spilt on it? And how long has the floor been laid?

 

[grumpy_cake]

Looks like oil. Has anything been spilt on it? And how long has the floor been laid?

Nope, we've been here for over a year and they started appearing probably after about 8 months, but it's been gradual. Originally I could get rid of them with elbow grease and a mop. We haven't spilt anything on it.... it wasn't newly decorated when we moved in so I would have thought it had been down at least a year before we moved in...