Hi, Hope someone can help. I purchased slates from my local supplier almost 10 years ago. Slates in question are Capco Eurocem B/B Slates 60x30. Unfortunately almost all the slates have now turned a horrible grey/white colour. The company "Comptoir du Batiment" in Belgium have agreed to respray them. However, I had thought that as they are still under 10 year guarantee the slates should be replaced. Unfortunately, I do not have a copy of the guarantee given with the slates and was wondering if anyone has had a similar experience. Any thoughts?