USATODAY.com – Big meteorite creates big mysteries < -source
By Bjorn Carey, SPACE.com
Scientists have discovered a beach ball-sized meteorite a half-mile below a giant crater in South Africa.
The 145-million-year-old meteorite, found in the Morokweng crater, has a chemical composition unlike any known meteorite.
It is also an unusual find because it was largely unaltered by the extreme heat from the impact.
The study is detailed in the May 11 issue of the journal Nature.
Oddball meteorite
Scientists have collected thousands of various meteorites over the years and tell them all apart by their various structural, chemical, and mineralogical compositions. The specific concentrations of platinum group elements in the newfound 10-inch (25 centimeter) meteorite place it in the “LL-ordinary chondrite” group of meteorites.
But other characteristics set it apart from the group, such as having silicate and sulfide minerals rich in iron, but no metallic iron-nickel phase.
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