Youndegin (Synonyms: Quairading, Penkarring Rock,
Mount Stirling, Mooranoppin)
The Youndegin iron
meteorite was originally discovered during 1884 in the form of
four pieces with weights of 2.7kg, 7.9kg, 10.9kg and 11.7kg.
They were found 1.2km Northwest of Penkarring Rock and 112km
East of York. In 1891 another mass of 173.5kg, and in 1892 a
still larger mass of 927kg were also found. Another huge
meteorite of 2625.3kg was found Southwest of Quairading, in
the vicinity of Wamensking Well, and is now assigned to this
fall. A further mass of about 92kg was located 40km Southeast of Mount Stirling
and is also assigned to this fall. A mass of 1.6kg was
found in about 1893, 97km East of York plus two further masses
of
820g and 742g. These three were referred to the Mooranoppin
fall, which is now considered to be synonymous with Youndegin.
It was actually named Youndegin after a police station which was
the last outpost of civilisation at the time.
Despite the
exceptional amount of material discovered, virtually nothing has
ever made it into private collections. Because this meteorite
was discovered a considerable time ago over such a vast area,
many of the pieces were initially named under their own fall.
The common synonyms for Youndegin include Quairading, Penkarring
Rock, Mount Stirling and Mooranoppin. The Total Known Weight of
all the Youndegin pieces is in excess of 3850kg.
Youndegin is an IAB iron meteorite
and has been classified
twice somewhat similarly as a Coarse (Og) and Coarsest (Ogg)
Octahedrite with a Nickel content of 6.8%. The main constituent
is the nickel alloy kamacite, in regular well defined plates
arranged parallel to the faces of a regular octahedron. The
widths of the plates vary from 1.5mm to 5mm but the average
Widmanstätten Bandwidth has been determined to be approximately
2.3mm. Simpson (1938) examined Youndegin and observed Cohenite
was “irregularly distributed as rather thick tablets and ragged
grains”. Schreibersite was fairly evenly distributed over the
etched surface as small irregular plates.
This specimen is a
complete slice which originally weighed 83g but after having the
piece professionally restored/prepared it now weighs 76.1g and is part
of the Meteorites Australia Collection (MA.05.0035).
Youndegin (IAB) - 76.1g Complete Slice
(Click image to enlarge in new window.)
Youndegin (IAB) - 76.1g Complete Slice
(Click image to enlarge in new window.)
Youndegin
(IAB) - Annotated Close-up
(Click image to enlarge in new window.)
Youndegin
(IAB) - Annotated Close-up
(Click image to enlarge in new window.)
Youndegin (IAB) -
Plain Macro View
Youndegin (IAB) -
Plain Macro View
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