Natural History - Cut and Polished Agate Crystal Geode End Group [4]

Containing several insects and other inclusions. 29.4 grams, 11.8 cm



From Madagascar. Acquired 1950s-1960s. From an old Bristol, UK, palaeontological collection.

An iron Campo Del Cielo (IAB) meteorite. 30 grams, 33 mm



From Chaco Province, Argentina, found 1576. From a Lincolnshire, UK, collection.

A crater field of roughly 26 craters was found in the vicinity of this crater, which is estimated to date to 4-5 thousand years BP. The age of the meteorite itself is thought to be c.4.5 billion years, formed as part of the development of this solar system. The largest two fragments, the 30.8 ton Gancedo and 28.8 ton El Chaco, are among the heaviest meteorite masses ever recovered on Earth. In 1576, the governor of a province in Northern Argentina commissioned the military to search for a large mass of iron, which it was believed the local people claimed had fallen from the sky and which they used for their weapon production. The expedition discovered a large mass of metal which was assumed to be an iron mine and brought back a few samples, which were described as being of unusual purity. Following the legends, in 1774 Don Bartolomé Francisco de Maguna rediscovered the iron mass. He himself did not believe that the stone had fallen from the sky and assumed that it had formed by a volcanic eruption. However, he sent the samples to the Royal Society of London. In 1990 it became protected by law.

A large section of Charonosaurus sp. hadrosaur egg nest on matrix, including three eggs each retaining some of the original shell surface. 17.3 kg, 43 cm



From a collection acquired on the UK art market from various auction houses and collections mostly before 2000. From an important Cambridgeshire estate; thence by descent.

Dinosaur eggs are known from about 200 sites around the world, the majority in Asia and mostly in terrestrial (non-marine) rocks of the Cretaceous Period. It may be that thick calcite eggshells evolved during the Cretaceous (145 to 65 million years ago). Most dinosaur eggs have one of two forms of eggshell that are distinct from the shells of related modern animal groups, such as turtles or birds; however, some eggs closely resemble the type of shells seen in present day ostrich eggs.