Thanks Pinfire, I inherited a few buckets of mixed opals including boulder and a whole lot of other roughs. Getting it all sorted has been a real headache and any help would be appreciated. I just wanted to confirm the origins before I sell, bit have been told its white lightning ridge. Ill post more pics.
First impressions Coober Peedy or Mintabie would come to mind, the fine fleck colouring and the flatness of the pieces, plus their size, but I'm far from an expert.