50 g Silver Cameroon 2022 - TENHAM METEORIT - Antique Finish Color 

*** Please Note : Delivery March 2023 ***

This marvellous Silver coin is dedicated to Tenham, a meteorite landed in 1879 in Australia. The coin has Antique Finish, features a pure Tenham meteorite insert and comes in a themed case with the Certificate of Authenticity. Limited mintage of only 777 pieces worldwide!
The reverse of the coin shows a crater created by meteorite Tenham in 1879. The meteorite landed in Australia and opened a new path for researchers of our planet and its history. At the center of the reverse, an authentic Tenham meteorite insert. The reverse also includes the inscriptions: “TENHAM” – the name of the coin and “AUSTRALIA 1879”.
The obverse of the coin shows the coordinates of the exact point where the meteorite landed in Australia. All around, the inscriptions: “REPUBLIQUE DU CAMEROUN” – the country of issue, “2000 FRANCS CFA” – the face value and “2022” – the year of issue.

Coin Data :

Cameroon - 2022 - 2,000 Francs - Mint of Gdansk - Antique Finish - Color

50 g .999 Silver

Legal Tender from Cameroon 
 

The Tenham Meteorit

Tenham is an observed meteorite fall in 1879, near Tenham Station in the Charters Towers region, Queensland, Australia.

The Tenham meteorite is a stony meteorite. The coordinates of the fall are now given as 25° 44′ 0″ S, 142° 57′ 0″ E.

Tenham has not been published in the Meteoritical Bulletin of the Meteoritical Society to date, but is officially recognised by the Meteoritical Society as an observed meteorite fall.

Fragments of the Tenham meteorite are preserved in the Smithsonian Institution's National Museum of Natural History (catalogue no. USNM 7703).

The discovery of a natural sample of the mineral bridgmanite in a fragment of the meteorite led to the official recognition of this mineral by the Commission on new Minerals, Nomenclature and Classification (CNMNC) of the International Mineralogical Association (IMA), which until then had only been known hypothetically as part of a group of silicate perovskites in the rocks of the Earth's mantle. The meteorite was found in the Tenham meteorite.

In addition to bridgmanite, akimotoite and ringwoodite were also discovered for the first time in the Tenham meteorite. The meteorite is therefore considered a type locality for these minerals.

Furthermore, the minerals chromite, diopside, native iron and its varieties kamacite and martensite, enstatite as well as hypersthene as a mixed crystal of enstatite and ferrosilite, ilmenite, isocubanite, clinoenstatite, native copper, lingunite, magnetite, majorite, taenite as well as plessite as a mixture of taenite and kamacite, tetrataenite, troilite, tuit, wadsleyite and wüstite were found in the meteorite. In addition, olivine and siliceous glasses such as maskelynite, among others, were present in the samples.

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Meteoroids/asteroids could deposit energy on Earth when they hit, which is of great concern. The scattering field as a product of meteoroid/asteroid break-up comprehensively reflects the trajectory, dynamics and physical properties of meteoroids/asteroids. They typically range in length from a few to a dozen kilometres. However, the recently found massive Aletai irons in northwest China comprise the longest known strewn field of ~430 kilometres. This suggests that the dynamics of Aletai may be unique. Petrographic and trace element studies indicate that all Aletai masses have a unique composition (IIIE-anomalous), suggesting that they originate from the same fall event. Numerical modelling suggests that the rockfall-like trajectory combined with a shallow entry angle (e.g. ~6.5° to 7.3°) is responsible for the exceptionally long scattering field of Aletai if a single-body entry scenario is assumed. The rockfall-like trajectory would not lead to the deposition of large impact energy on the ground, but could lead to dissipation of energy during the extremely long flight.