- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
"The discovery of fossil opal-phytoliths in several Tertiary and Quaternary sediments of Victoria shows that they resisted mechanical and chemical weathering during deposition. They survived several million years without being severely corroded or transformed by hydration to either chalcedony or quartz during the diagenesis of sediments. Fossil as well as recent plants secreted opal-phytoliths. Their presence in sediments serves as an indicator of certain plant groups, grasses, reeds and their allies, where recognizable remains or macerated debris did not survive."