Flagstone instead of waterline tile?

[fyton2v]

I'm using a very hard quartzite flagstone for my pool decking and coping. There is plenty of info out there on how flagstone may fail over a short amount of time due to constant evaporation after coming into repeated contact with pool water. However, it seems that this problem has more to do the type of flagstone used along with water chemistry than anything else.

I'm wondering what some of the opinions are from the pool experts of this forum. Is it crazy to consider using this stone in place of tile at the waterline? In terms of hardness the particular flagstone i'm using is probably harder than Three Rivers. How long would sealing last?

Thanks...

 

[JasonLion]

Flag stone is a category of stone, rather than a specific stone. Stone that is easy to cleave into flat slabs, suitable for use as decking or capstones, called flagstone. In practice, flagstone usually means a relatively soft kind of stone that splits easily, which is not at all suitable for use as a waterline tile replacement. Some flagstone is actually sturdier stuff that would work, since occasionally other store that isn't so easy to make into slabs is called flagstone just because it was made into slabs, but that is unusual.

I would be very hesitant to use anything labeled flagstone as a waterline tile replacement. It is possible that your stone will work out in that use, but it is unlikely and there is no way to be sure without talking to a stone expert who knows exactly what kind of stone you are trying to use.

 

[CraigMW]

We have flagstone decking and coping around our pool. The one thing I'd be concerned about is efflorescence. Many of our coping stones show a white powder-like staining on the sides towards the water that I believe is due to calcium buildup over several years. Below that is standard ceramic tile, which looks fine. I would imagine similar white blotches on any natural stone tile in contact with the water.

 

[JamesW]

Another thing you need to consider is how easily the tile line can be cleaned. Glazed ceramic tile is easy to clean, whereas a more porous stone would absorb body oils and such and would tend to accumulate a black dirty line that would be more difficult to clean.