Natural History - Mini Agate Crystal Geode Cut Half Group [100]

A vertebra with neural arch from the dinosaur Deltadromeus agilis. 247 grams, 87 mm



From the Kem-Kem Basin, Morocco, North Africa. From an old German paleontological collection.

Deltadromeus meaning 'delta runner' has extraordinarily delicate and long limbs making it one of the fastest dinosaurs to have existed. This meat-eating dinosaur is an early off-shoot of the theropod line on northern continents that gave rise to Tyrannosaurus and the raptor Deinonychus.

Two Green River fish specimens Diplomystus sp. in a matrix. 243 grams, 15.8 cm



From Wyoming (Green River Formation), USA. From a Lincolnshire, UK, collection.

In southwest Wyoming (and parts of Colorado and Utah) in the Green River Formation are found some of the world's most outstanding specimens of fossil fish. The Green River system was composed of three lakes: Lake Ulinta, Lake Gosiute and Fossil Lake. These Eocene lakes lay in a series of intermountain basins formed by geological events that uplifted the Rocky Mountains during the early Tertiary time. The climate was much different from the desert-like climate of this area today. Both the fauna (crocodiles, alligators, boa constrictors and some subtropical fish families) and the flora (such as large palm trees) indicate a climate much like that found along the Gulf Coast today. Large amounts of ash found in the sediments indicate that volcanoes were particularly active at this time.

Comprising two cut and polished Aegasteroceras sagittarium ammonites showing good detailing. 261 grams total, 70-96 mm



From Conesby Quarry, Scunthorpe, UK. From a Lincolnshire, UK, collection.