Kuratite: New Mineral Discovered in Meteorite

he stony meteorite D’Orbigny is the source of a newly discovered mineral,kuratite. Its name honors Dr Gero Kurat (1938-2009), a world-renowned meteorite researcher and long-term head of the Mineralogical-Petrographical Department at the Natural History Museum in Vienna, Austria.

This image shows a fragment of the D’Orbigny meteorite. Image credit: Jon Taylor / CC BY-SA 2.0.

The meteorite D’Orbigny, a 16.55-kg stone mostly covered with dark gray fusion crust, was found by a farmer plowing a corn field in July 1979 in Buenos Aires, Argentina. The object was originally thought to be an Indian artifact and it remained on the farm for nearly two decades before speculation arose that it might in fact be a meteorite.

Confirmation of it’s extraterrestrial status was finally achieved in 2000 after a sample was analyzed by Dr Kurat and his colleagues.

The meteorite was determined to be an exceedingly rare achondrite known as an angrite. It is characterized by prominent vesicles which are rarely seen in meteorites.

In 2004, Dr Kurat with co-authors published a paper in the journal Geochimica et Cosmochimica Acta, in which they also reported on the occurrence of an unidentified iron-aluminum-titanium-silicate in the meteorite D’Orbigny.

This is a fasle-color micrograph showing kuratite (Ku) crystals embedded in the D’Orbigny meteorite. Image credit: Hwang SL et al.

This unknown mineral phase consisted of very tiny crystals with an average diameter of only about 0.01 mm.

Because of the small size of the available material it was very difficult to determine all relevant chemical-physical properties, which are required for a mineral phase to be accepted as a new mineral.

In a new study, reported at the 45th Lunar and Planetary Conference in Houston, Texas, scientists led by Dr Shyh-Lung Hwang of the National Dong Hwa University in Hualien, Taiwan, were able to identify the unknown mineral as kuratite.

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Hwang SL et al. Kuratite (IMA 2013-109): The ‘Unknown’ Fe-Al-Ti Silicate from the Angrite D’Orbigny. 45th Lunar and Planetary Science Conference. LPI Contribution no. 1777, p.1818

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