I am attempting to lay marble tiles over an existing slate quarry tiled fireplace.
My neighbours have undertaken the same project recently and used an adhesive more like liquid nails then regular thinset.
They said they were advised to use this as the substrate will expand and contract with use.
Can anybody recommend a thinset or adhesive that would be suitable for use on a fireplace and also will bond with slate quarry tiles.

Thanks

TilguyBob may give you some advise on tiling. My question is - why are you putting marble Over the slate? Why not remove the slate, so that you are working with a smooth, non- expanding surface? Doesn't the double thickness give a non-uniform look? Is this on the hearth or fireplace surround? Or both?
Marble is a more fragile stone, and I can't picture it laid over slate.

I attempted to remove the slate but it is glued to the wall underneath and can't be removed without damaging the wall, lumps of plaster come away with the tiles.
I'ts both the hearth and the surround I will be tiling with marble.
Thinset manufacturers and Home Depot recommended Megaflex, Flexbond or Marble and Granite.

Interested in knowing how your fireplace is coming along? I just bought a home that has a marble fireplace. I'm wanting to place tile over the entire marble, but was told that the marble may be too slick of a surface to have the tile stick to it. interested in knowing how yours turned out..

Thanks

First off, ALL surfaces will expand and contract, especially with the extreme heat from a fireplace, not just slate. As for a good thinset to use, My pick would be an unmodified thinset mixed with a liquid latex additive, such as Laticrete's 317 thinset mixed with their 333 liquid, full strength.

beatspecific-- not a problem. Hit the marble with an orbital sander to scruff it up, and you're good to go, with the same kind of thinset I just described.

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