The process of opalization refers to something turning into an opal — like for example, a big part of this fossil. Opalized ammonite fossils are formed through a unique geological process ...

NASA’s Perseverance rover has uncovered high-purity quartz crystals on Mars, a discovery that could reshape the search for ...

Other fossils include: turtles, crocodiles, fish, birds, early mammals, mussels, snails, giant marine reptiles, pine cones, plant stems and seeds. The Australian Opal Centre has 4000 or more fossils ...

There are few fossils, but even they create controversy. The opal fields of Lightning Ridge in New South Wales have produced a few jaws and teeth of small monotremes. Steropodon and Kollikodon are ...