This is a untreated opal rough mined in lightning ridge and direct from the miner. This was mined in a field called allawas.
This was once vegetation or wood 100 million years ago. With some wood fossils there may be inclusions in the stone which i think is best to leave in the stone.
I have thousands of rough stones in my store SEDA ROUGH OPALS but you can only combine with stock in this store. I suggest you look at the rough dry and wet before cutting as we only refund on untouched rough.