I am trying to find out what type of paint to use as I a have a number of Japanese StyleGarden ornaments around my pond including a bench. These are concrete and are finished in a Matt Jade Green. I thought of having a colour mixed in Smooth Masonary paint but have been advised that as rain'sits' on the bench the masonary paint would lift off. I want to keep the matt effect can anyone advise what type of paint to use?