Al Haggounia EL3 Meteorites for Sale
Location: Al Haggounia, Morocco (27° 30'N, 12° 30'W)
Classification: Enstatite Chondrite (EL3)
Description: There are two kinds of Al Haggounia, a rusty friable extremely weathered variety with significant quantities of secondary minerals and a light bluish-gray apparently fresher-appearing, but still very weathered kind. Ted Bunch and Tony Irving describe "The Al Haggounia "Fossil or Paleo" Meteorite Problem" in an extensive web page that can be found at the link. The meteorites for sale here are the "fresher" variety. These match the description of NWA 2828 as revised and published at the above link. That description is copied below. Originally, this meteorite was classified as an aubrite, but the presence of chondrules lead the original classifiers to change their opinion. Also, I would not call these pieces "fossil" meteorites as the mineral constituents present are part of the original rock rather than being replaced. Iron has been preferentially weathered out.Physical characteristics: 160 pale gray to whitish stones lacking fusion crust with a total weight of 34.19 kg. Most stones have exterior light orange staining, and some stones contain dark brown rinds or cross-cutting veins (1-2 mm wide) of magnetic, fine grained iron oxide and hydroxide minerals. Several stones have pink terrestrial rhyolite pebbles attached to them by a sandy matrix, indicating that the meteorite stones are cobbles in an ancient conglomerate bed.
Petrography: (A. Irving and S. Kuehner, UWS; T. Bunch and J. Wittke, NAU): Relatively fine but variable grain size (0.3 to 1.5 mm), and composed predominantly of prismatic grains of essentially pure enstatite (untwinned) with ~15 vol. % oligoclase, accessory iron sulfate pseudomorphs after troilite (with fresh, subparallel exsolution blades of daubreelite) and sporadic rounded to ellipsoidal grains of graphite (up to 1.2 mm across). Several stones contain sparse, round RP chondrules (up to 2 mm across) and sporadic whitish, rounded, fine grained clasts (up to 6 mm across) rich in either enstatite or sodic plagioclase. Small (0.5 -1 mm) lobate cavities partly coated with fine grained calcite, halite, gypsum and iron sulfate are present in the interior of even the freshest stones. Small grains found as inclusions within enstatite are fresh Ti-free troilite, pure Mn-alabandite, daubreelite, fresh oldhamite (some Mn-bearing), schreibersite, and very rare specks of kamacite and taenite. Minor barite is present.
Geochemistry: Pyroxene (En98.4Wo1.4, Al2O3 = 0.21 wt. %), plagioclase (An13.5-15.3Or3.0-4.4). Oxygen Isotopes (D. Rumble, CIW): Analyses of two acid-washed whole rock fragments by laser fluorination gave, respectively, δ18O = 5.50, 5.56 ‰ ; δ17O = 2.89, 2.90 ‰; Δ17O = -0.001, -0.026 ‰.
Classification: The presence of sparse but well-formed enstatite-bearing chondrules containing glass (mostly dissolved) and the lack of recrystallization of the matrix make this an EL3 chondrite. Based upon the replacement of troilite by iron sulfate and complete dissolution of primary metal, the weathering/diagenetic grade is W4. This material is the less weathered equivalent of material classified as NWA 2965 (Kuehner et al., 2006).