Looks like it’s over in Mintabie. Mintabie township has been closed and evacuated. The land where the opal mining town of Mintabie resides has been leased by the South Australian State Government from the APY (Anangu Pitjantjatjara Yankunyjatara peoples) has been released back to the APY and thus closed to anyone except the APY peoples. You can read all about this here: Mintabie Closure .
A survey done several years ago by the The Geological Survey of South Australia found some interesting indications on the opal mining potential of the Mintabie area:
ABSTRACT The Mintabie Precious Stones Field (MPSF) has, since the early 1920s, produced some of the finest quality opal in the world. This report book provides a review for understanding the remaining opal resources. A detailed spatial analysis shows that after approximately 40 years of mining in the MPSF, an area totalling less than 2 square km has been intensively mined. A conservative estimate of the area of greatest prospectivity within the MPSF is 20 square km. Within this region of high prospectivity, assuming a similar deposit density to the intensively mined areas to date, the MPSF will support mining for ~400 years at the levels already experienced in its lifetime. Complimentary analysis published in 2002 reveals further prospective regions within the MPSF totalling 44 km2. The total value of the opal mined at Mintabie up to 2016 has been estimated by the South Australian Government to be $412M (un-adjusted value of rough opal). An area-based analysis concludes that this is less than 10% of the total contained opal at Mintabie. The opal resource in the MPSF, including the opal already found, is therefore estimated to have an un-adjusted raw opal value of over $4B.