Hi m8 welcome
Inorder to see what is going on here you have to understand how travertine works.
Travertine is sedimentry limestone so is basicaly made up of layer upon layer of sediment like shells etc and small grains built up as water bubbles through it and is consolidated under the weight of the layers, the way its formed leaves it porous.
When travertine is cut its first chopped into blocks then sheets from which the tiles are cut. Now think of cheese like Gouda full of holes. As its sliced you cut across the holes which are evident untill you come to the end of a hole. When this happens you can have a thin piece in the middle of your slice which looks ok but isnt as thick as the rest. Ok now back to travertine. The travertine is sliced into slabs and the surface holes filled with a compound before it is honed smooth. When you pick up the slab it looks cool BUT remember the cheese there may be areas where the Travertine has been cut through the end of a hole. You have a weak spot.
A propotion of trav is good quality and the tiles are heavy but far too much is light and not very dense. It is the lighter cheaper trav which shows this problem most often.
To combat this you can do 2 things 1st you buy cheap you get cheap so buy quality travertine 2nd always butter the back of the tiles filling any voids when you are fixing
Easy isnt it
tiler
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