924 grams. Diogenite-olivine
Fall not observed. Found 2007.
Location Map of Antarctic Falls
AMN writes:
Macroscopic Description - Roger Harrington
Dull black fusion crust covers 40% of this achondrite’s exterior. Approximately 40% of the exterior is a tan to medium olive green with a fine grained matrix. 20% is medium to light olive green with a coarse grained matrix. One 3 mm diameter dark mineral inclusion is present on the top north side. Cleavage planes are visible on the inclusion when viewed under a hand lens. The interior is a medium gray to orange tan fine grained matrix with less than 1% small (<1 mm) dark mineral inclusions.
Thin Section Description (,7) - Tim McCoy and Linda Welzenbach
The section is unbrecciated and is dominated by 0.5-1 mm equigranular orthopyroxene with abundant 120° triple junctions. Olivine occurs as rounded grains both interstitially to and poikilitically enclosed in the orthopyroxene. Opaques included oxides, troilite and metal. Orthopyroxene has a composition of Fs23 Wo2 and olivine is Fa28. The Fe/Mn ratio of the pyroxene is ~30. The meteorite is an olivine diogenite.
Oxygen Isotopic Composition - Z. Sharp, University of New Mexico
Oxygen isotopic analyses of two splits yielded the following results which fall in the HED meteorite field. All samples were cleaned in a 10% HCl solution for 1 minute, followed by ultrasonication.
ä17O = 1.64, ä18O = 3.80, Ä17O = -0.33
ä17O = 1.34, ä18O =3.55, Ä17O = -0.50
[where Ä17O = ä17O – 0.52 x ä18O]
|