with but now we have had several pools where the coping is disintegrating.The tops of the stone are peeling like sun burn and the front edge, which is a chipped edge to start with, is now worn smooth and is powdery on the surface. A pool which was finished a year ago and the stone work sealed with a high quality stone sealer is now showing major deterioration from salt.Another pool which is about three years old has a -or should i say had a-dark gray sand stone coping which was a very hard sandstone. About 20% of the coping is almost white with the salt sunburn peeling in several places. This stone was not sealed with a sealer.
We are also seeing the effects of salt on our limestone coping. It is bleaching out and becoming splotchy and only on pools with salt systems.
Pools we have built and used travertine coping have had no noticeable effects. This stone has been honed and filled so it is not porous and seems to be unaffected by the salt.
We have tried cleaning the surfaces but it seems once it is in the stone it is like a cancer that keeps deteriorating. Customers expect this to be corrected,new stone installed to replace the old, but there is no way to determine if the new stone will be resistant -even with sealer- to the effects of salt water.
I now feel a little chlorine and a UV generator might be a better option when using sandstone around a pool,especially when the replacement of the stone is expensive and there is no assurance the replacement will be any better.