Making a smooth edge slate tile harrassed/rustic looking

[JuJuDreamy]

I have some slate roof tiles that I'm looking to make into placemats (no cutting required - just as is) and coasters. I hope to make 6 coasters (4.5" x 4.5") which I'll need to cut out of the slate but my problem is with making the smooth cut sides feathered or rustic looking. It may be a different word altogether but I think the rustic look is better than smooth sided.

Do you know of a tool I can use to create this effect (bearing in mind that I'm a 31 year old woman!) and not very handy with a hammer and chisel. I can't afford also for it to be time consuming as I have a 1 year old daughter too.

If you could help me out with my question, I'd be most grateful.

[muffs11]

buy some slate cutters from a builders merchant