Our attractive Diplomystus Dentatus fish frame measuring 735mm, an ancestor of the herring family, a very finely boned fish which is extremely difficult to prepare from the Lagerstätte varve layer of the Eocene limestones of the Green River formation 18-inch layer.

The lower Eocene deposits of Green River formation was thought to be a large freshwater lake or lagoon which suffered from occasional falls of volcanic ash which smothered the lagoon and helped to create an anoxic environment. This reduction of oxygen suffocated the inhabitants of the lake and in the process, preserved such specimens exceedingly well. This presented the perfect preservation process for flora and fauna alike, deposited within the silts at the bottom of the lake which eventually transformed into soft calcite bearing shale, eventually absorbed into these flora and fauna specimens, transforming these into the pieces they are today.

The eighteen-inch layer is a lower Eocene varve layer, is not fissile laminae and therefore much more difficult to split and work successfully, older in the fossil lakes system containing fish which have been preserved which calcite mineralisation. The mineralisation is caused by absorption of localised mineral elements being absorbed by the process of osmosis. Water coursing through the mud layers at the time of deposition deposited minerals in the tissues of the fish, in this case, its skeletal elements, bones teeth and cartilaginous parts. In this 18 inch layer, this exhibits in a dark calcite skeleton encapsulated in light coloured limestone of the Lagerstätte fossil varved lime muds. The mineral preserves every fine detail of this particular fossil bed, a very rare occurrence indeed.

The details

Genus: Diplomystus Dentatus.
Age: Paleogene, Eocene, 53.500,000 to 48.500,000 years.
Origin: The Rocky Mountains, Lake Gosiute, Green River, Wyoming, USA.

Frame: H: 47.5 CM / W: 73.5 CM / D: 5 CM / KG: 10.321