Hi, Mike,

I would post your question on a tile forum @ Johnbridge.com. There are come real experts there that may have a definitive opinion.

Travertine, while it looks great, I know to be one of the problematic natural stones to hold up in an outdoor environment....it's pretty soft. It may be perfect for you but I think you may have to deal with some issues of maintenance and longevity......perhaps not enough to keep you from using it but a factor, nevertheless.