Not really except that slate does tend to flake under temp and humidity extremes. It is also somewhat brittle so make sure your surfaces are level and your tile thick enough or it could crack on you. You should be fine though. Do mind the weight also. Slate is heavier than ceramic and even marble as I remember.
You will probably want to to seal it for bathroom use? I've never speced it for a bath so hope someone who has will respond here.
I've worked on antique homes with slate roofs over 100 years old that still, save for a bad tile here and there, look and work great.
Slate comes in many variations. Most of which should not be used in a wet area such as a shower. They will delaminate. Black slate is a more silt based stone that will not come apart at the seams, so to speak.
If you pick a stone for the shower, just realize, it requires sealing on a regular schedule.
Slate is a bad idea in a shower. It is porous and will collect mineral deposits from the water and soap scum that will be very difficult to clean if possible at all.
If you are thinking about using the cheap slate available at the home centers that product is the worst. In addition to the flaking and other above issues, that slate also harbors iron deposits and will rust everywhere the water drains. Sealing it will not help.
There are many porcelain ceramic tiles available that mimic slate and those are your best bet.
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