I bought some patio stones. They were made out of cheaper cement and they are very fragile. I studied a broken one before I threw it away. The cement is held together with stringy, plastic mesh. If they were using cheap cement, that may be a factor.
Do you know there was a cement short during the construction boom last year? I'd want info on the cement.
So far, crickets chirping on the grade of cement and no reporters have asked about it that I've seen.