Lot 56
Estherville
The Robert Elliott Meteorite Collection
Auction: 18 August 2009 at 15:00 BST
Description
Polished part slice
Dimensions
6.95kg, 34.6 x 30.9cm
Footnote
Estherville (Emmet County, Iowa, USA) Mesosiderite (stony-iron) - fell 10th May 1879
A bright fireworks show announced the arrival of this witnessed fall, and the explosive detonations that followed were reported to be loud enough to stop an argument during an Estherville baseball game!
This stony-iron is called a mesosiderite: broken mantle rock composed of angular rock fragments of different compositions. Large nuggets of nickel-iron can be found in Estherville, as well as stony inclusions that can reach sizes of several inches across. As their mineral compositions are unrelated, mesosiderites can be troubling to scientists - a current theory describes the reassembly, accretion and mixing of the components after the collision of two asteroids in space, followed by heating under pressure, melting and crystallisation over a very slow cooling period.
Provenance: Natural History Museum, London