Ammonites were shelled cephalopods that died out about 66 million years ago. Fossils of them are found all around the world, sometimes in very large concentrations. The often tightly wound shells of ...

Based on the fossil record, ammonites came in a wide range of sizes and shapes, from smaller than an inch to as large as nine feet wide. Some ammonites had long, straight shells, while others had ...

In fact, iridiscent opalized ammonites are so striking that they have their very own mineral name: ammolite. Ammolite is biogenic gem material primarily found in Alberta, Canada. However ...

This Jurassic ammonite looks like it has been dipped in gold, but its colour is due to the mineral iron pyrite (often referred to as fool's gold) In Hindu culture, black limestone concretions ...

As Earth formed, new geologic processes, especially those related to the interaction of hot fluids with rock during igneous activity and plate tectonics, gave birth to over 1500 new mineral ...