e have never done that, but we think you can do that, but you might need to use a mixture called laticrete in your concrete mixture. However, do not use the laticrete in your cement joints. That will look horrible.
Also, keep in mind about the weight underneath. Make sure that your plyboard can support your stone and concrete. Usually you use Dura-rock for tile, so make sure that your stone is not too heavy.
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