• NWA 2977 is a lunar gabbro meteorite that contains two pyroxenes, olivine, plagioclase shocked to maskelynite, K, Ba feldspar, and various Cr, Fe, Ti oxides. This cumulate lunar rock (cumulate = accumulation of crystals by gravity settling in a magma) probably originated in the lunar highlands environment as a thick lava flow or as a shallow intrusive into the highlands crust. After formation, the gabbro was moderately shocked by hypervelocity impact.
  

  
  

   

  Official Classification from Meteoritical Society Data Base

  Northwest Africa 2977

  Morocco or Algeria

  Find: 2005 November

  Achondrite (Lunar gabbro)

  History: A single minimally weathered, fusion encrusted stone of 233 g was purchased from a Moroccan dealer in Tagounite, Morocco by M. Farmer in November 2005. Petrography and Geochemistry: (J. Wittke and T. Bunch, NAU; A. Irving, UWS) The specimen consists of a single yellow-green, relatively coarse-grained rock traversed by thin, black glass-rich, thin veins.  It is an olivine-rich, two-pyroxene cumulate gabbro composed of olivine 51%, Fa_31.7, FeO/MnO = 96; pigeonite 23%, Fs_26.6Wo_6.7; augite 9%, Fs_16.2Wo₂₉; plagioclase 14%, An₅₆ with minor amounts of Ba-K-feldspar, chromite, ilmenite, and merrillite. Larger pigeonite grains commonly enclose equant olivine grains, which contain abundant melt inclusions (0.025 to 0.125 mm).  Plagioclase is partially converted to maskelynite, and pyroxenes and olivine exhibit shock lamellae and undulatory extinction.  Noteworthy This specimen is identical in texture and mineral compositions to the gabbro clasts in NWA 773 and NWA 2700 and thus appears to be paired with those breccia specimens.  Classification: Achondrite (Lunar gabbro) with minor weathering.  Specimens: A 20.1 g specimen and one polished thin section are on deposit at NAU. A 0.5 g specimen is on deposit at WUSL. An anonymous owner holds the main mass.

Abstract submitted for presentation as poster at the LPSC in Houston in March, 2006.  PDF document. requires an Acrobat Reader (it is free):

LUNAR METEORITES NWA 2700, NWA 2727, AND NWA 2977: MARE BASALT/GABBRO BRECCIAS WITH AFFINITIES TO NWA 773.  T. E. Bunch, J. H. Wittke, R. L. Korotev, and A. J. Irving, Dept. of Geology, Northern Arizona University, Flagstaff, AZ 86011, Dept. of Earth & Planetary Sciences, Washington University, St. Louis, MO 63130, Dept. of Earth & Space Sciences, University of Washington, Seattle, WA  98195

233 gram meteorite before cutting.

19.4 gram main mass endcut:

Click images to enlarge:

Cut face measures 44.3mm by 22.5mm.  Depth of endcut is 17.9mm

  Sample of Certificate of Authenticity.

  Sample of ID card.