Prof Patrice Rey from the School of Geosciences at the University of Sydney has described for the first time the dramatic geological events that created the Australia’s national gemstone. Alaric opal mine is located within the weathered sandstone and mudstone of the Winton Formation, Queensland. Opalized horizon corresponds to a flat pre-late Paleocene paleosurface, buried underneath Cenozoic sediments (P. F. Rey, 2013) Australia produces over...
