Polished Citrine Crystal Specimen Group [47]

Comprising four specimens with popcorn-like formations of white crystals. 536 grams total, 4.9-10.2 cm



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

Cut half Cleoniceras sp. ammonite, polished to reveal the distinctive structure of the chambers, some iridescence to the outer shell. 108 grams, 10.4 cm



From Madagascar. From the private collection of Kenneth Machin (1936-2020), Buckinghamshire, UK; his collection of antiquities and natural history was formed since 1948; thence by descent.

Comprising two complete Knightia alta specimens and remains of a third fish. 622 grams, 13.1 x 13.7 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.