I had a new kitchen fitted last year and it's lovely. At the same time I had the 70s lino replaced with beautiful slate tiles. But the bloody things ALWAYS look grubby - I mopped them half an hour ago after a messy supper with dd and they look filthy.
Is there anything you can seal them with to help protect them and give them a sheen? The floor was v expensive and is beautiful, just.... muddy looking.