Natural History - Polished Amber with Insect Inclusions

A cut and polished septarian egg half, the centre filled with calcite crystals surrounded by a thin layer of aragonite, the outer layer of grey limestone; a beautiful display piece. 3.8 kg, 20.5 cm



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

A pair of Knightia alta fossil fish in a matrix. 336 grams, 12.6 x 11 cm



From Wyoming, Green River Formation, U.S.A. Acquired during the 1980s. From the Pradi Collection, Boston, U.S.A.

Seasonally, some 56 million years ago, in the Green River Region of Wyoming, torrential rains fell on the mountains. The rain flowed down the mountain sides, forming wide shallow lakes in the valley below. During the dry season, these lakes evaporated (similar to certain parts of Africa today). Millions of fish died in this short period of time. This climatic cycle happened over a 20-thousand-year period. Layer upon layer of mud was deposited over these years, entombing huge numbers of fish. At a much later date volcanic activity uplifted this area to expose their fossils.

A group of eight black meteoritic tektites with pocked surfaces. 257 grams total, 37-68 mm

Fine condition.

Ex UK art market, 1970s. Property of a London gentleman.

Tektites are lumps of black or dark grey natural glass produced from melted crustal rocks that are caused by large hypervelocity meteorite impacts on sediments.