Natural History - Large Amethyst Crystal Chunk Group [12]

Each cut to reveal an internal crystal-filled cavity and banding; in enhanced dark purple colour. 772 grams total, 84-94 mm



Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's).

Comprising three large fossil Onchopristus numidus sawfish rostral teeth. 21 grams total, 47-53 mm



From in the phosphate mine region, Khouribga, Morocco, North Africa. From a Cambridgeshire, UK, collection.

With a shoal of Knightia alta sp. specimens, some preserved on top of each other, on an irregular matrix; mounted on plywood backing. 42.9 kg, 117 cm wide



From Wyoming (Green River Formation), USA. Property of a Cambridgeshire, UK, gentleman.

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.