Tullimonstrum gregarium, Tully Monster Mammoth / Mastodon Malachite is also found as

Malachite is also found as a pseudomorph

pyrophyllite

as there's an amazing array of colors and tones within each individual stone

~ 5"  x  5"  x  2" high

The Paleolithic era

Tullimonstrum gregarium, Tully Monster Mammoth / Mastodon Malachite is also found asTullimonstrum gregarium, popularly known as The Tully Monster, is the Illinois State Fossil & is perhaps one of the most mysterious fossils ever unearthed Age of the Tully Monster During the Pennsylvanian Period (roughly 307 million years ago), the land that is now Illinois lay near Earth's equator. Dense swamps, forested with primitive plants, covered much of western and central Illinois. In shallow seas nearby, the Tully monster swam along with