Large Group of One Hundred [100] Amethyst Crystal Sections

Attractive group of polished translucent slices showing contrasting bands, two showing quartz crystal formations, and with dendritic inclusions and four with horizontal banding. 795 grams total, 9.2-12.7 cm



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

An irregular matrix with Ophiuroidea sp. specimen. 1.63 kg, 23.2 cm



From a Lincolnshire, UK, collection.

Comprising three roughly oval matrices with Knightia alta specimens. 165 grams total, 70-74 mm



From Wyoming, 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 Uinta, 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.