One of the people I met at the Hong Kong show last month was a real genuine opal miner from Australia. Her mine (yes, female) produces some absolutely stunning stones. If you want opals with a impeccable provenance then Sue Cooper is your lady. You can see a video I posted with a reveal of raw opal as a vein in a piece of rock and a photo of her on the Pearlescence instagram page
I'm sorry I can't post the photo and video direct because they are on my phone which is sitting in silica gel having got wet...
Look also at or @brokenrivermining