Hi
The ply will need priming as per adhesive manufacturer.
An uncoupling membrane is recomended when stone is going onto wood and new screeds.......... Due to the stones make up it has weaknesses which are easily effected by latteral movement causing cracking.
Another consideration has to be weight as if it is Marble it will be cut at thicknesses over 15mm so heavy.
Pre-sealed stones are few and far between however there are stones pre-sealed with lithofin available...........The floor will need sealing again when finished............NOTE check what sealer has been used so you can finish with a compatible one
tiler
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