Linoleum Floor Tile Issue
My site has encountered an issue with its linoleum floor tiling and no one is sure about the cause. Here's a linked folder with images detailing the issue. Sorry its not embedded, some weird requirement prevents me from doing it.
In short there appears to be dirty, abrasive spots forming at the seams of where adjoining tiles meet. This issue is seen through the site and predominantly on the ground (1st) floor.
Any ideas what this issue is a result of?