Mintabie opal resource evaluation: Current value of opal resources and projected value of undiscovered resources
Mintabie opal resource evaluation: Current value of opal resources and projected value of undiscovered resources Report
- Author(s): Katona, LF, Krapf, CBE
- Published: 2020
- Publisher: Department for Energy and Mining
- Edition: 2nd edition
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 km2 has been intensively mined. A conservative estimate of the area of greatest prospectivity within the MPSF is 20 km2. 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 (unadjusted 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 unadjusted raw opal value of over $4B.