NWA 6077 is a unique and fascinating meteorite that is an ungrouped achondrites that shares some affinities with the brachinite group. This meteorite originates from a primitive, unknown parent body that may no longer exist. There has been some speculation in the scientific community that NWA 6077 (and it’s likely pair NWA 5400) may be an “Earth meteorite” that was ejected from our planet in the distant past by a massive impact, and then fell back to Earth as meteorites.
This unusual meteorite was recovered out of Morocco in 2008 and submitted for classification to Dr. Tony Irving and was given the classification number of NWA 6077. This meteorite has a modest TKW of less than 1000g after the type specimen was removed. Elemental analysis of NWA 6077 has shown the presence of olivine, clinopyroxene, kamacite, chromite, chlorapatite, minor amounts of nickel (in the form of iron sulfides) and troilite.
Refer to the photos. The black centimeter cube is shown for scale and is not included. You are purchasing the specimen shown. It is a slice that weighs .202g (202mg). One of the cut faces has been polished. Your purchase will include a labeled gemjar for safe storage.
From the Meteoritical Bulletin entry on NWA 6077 :
Northwest Africa 6077 (NWA 6077)
Purchased: Sept 2008
Classification: Ungrouped achondrite
History: Purchased September 2008 by John Higgins from a Moroccan dealer in Agadir.
Physical characteristics: A single brownish 1010 g stone.
Petrography: (A. Irving and S. Kuehner, UWS) An olivine-rich assemblage with protogranular (possibly cumulate) texture exhibiting triple-junction grain boundaries. Additional minerals include orthopyroxene, clinopyroxene, altered kamacite, chromite, chlorapatite, Ni-bearing troilite and/or pyrrhotite. No plagioclase was found.
Geochemistry: Olivine (Fa30.2-30.7), orthopyroxene (Fs24.1-24.5Wo2.1-2.0), clinopyroxene (Fs9.4-10.0Wo44.0-43.5). Oxygen isotopes (D. Rumble, CIW): δ17O 2.667, 2.932; δ18O 5.180, 5.536; Δ17O -0.057, +0.020 per mil
Classification: Achondrite (ungrouped, brachinite-like). Specimen exhibits similar mineralogy and oxygen isotopic composition to NWA 5400, and is likely paired with it.