👉 Endoceratite is a type of mineral that forms in the Earth's crust and has been known since ancient times. It is composed of calcium carbonate, which is found in sandstone and other rocks. Endoceratites are typically dark green or brown in color and have a smooth surface. They can be found in various shapes and sizes, including spheres, cylinders, and cubes. Endoceratite has been studied by scientists for thousands of years and is still being researched today