Can I stencil with chalk paint on black tile which hasn't been primed?

You should be able to try a small area

You can try it. If the tile is shiny it may scratch off or wipe off. If it is tile that you are walking on I don't think it wear well. You will have to seal the chalk paint stencil design with a clear sealer or poly.

If it's a porous tile, then yes. If it's shiny ceramic, the paint will scrape right off.

Should able to! try on a small area first. You will have to seal it though as it will chip off pretty fast

You can but primed wall will give you much better results. Just telling you with my personal experience. Good luck

Bushra