uneven boulder Opal

[theresa]

I have a very uneven boulder to set and wondered if I put some blue tack underneath if this would work?
I can't play around with the Opal very much because the layer of Opal is very thin and I am worried in case it chips (again). I had to send it away to be re-polished and it now looks fab. I am not going to set client's stones any more, much too stressful....