from The Meteoritical Bulletin, No. 111
Northwest Africa 14657 (NWA 14657)
Lunar meteorite (feldspathic breccia)
History: Purchased by Edwin Thompson in early 2021 from a meteorite dealer in Adrar, Algeria. Subsequently acquired in May 2021 by Cascadia as part of a trade..
Physical Characteristics: Single stone with nearly absent fusion crust.
Petrography: (D. Sheikh, H. Babst, Cascadia) Sample displays a brecciated texture composed of lithic clasts (most mm-sized, up to ~1 cm), mineral clasts, and isolated mineral fragments set within a fine-grained matrix containing glassy melt pockets and fractures. Various anorthositic clast lithologies (ferroan anorthosite, magnesian-suite anorthosite, and hyper-ferroan, as found in ALHA 81005, Dhofar 302, Dhofar 081, and NEA 001 by Gross et al. (2014) were identified in this sample. Accessory phases include ilmenite, apatite, silica, troilite, ülvospinel (some Cr-bearing), and Fe-Ni metal. Some plagioclase grains have been transformed into maskelynite.
Geochemistry: Olivine (Fa34.1±8.1, range Fa19.9-40.4, Fe/Mn=87±6, n=26), Low-Ca Pyroxene (Fs24.3±6.0Wo3.2±1.1, range Fs16.6-29.8Wo0.3-4.5, Fe/Mn=51±4, n=12), Pigeonite (Fs40.3±11.8Wo13.5±5.7, range Fs22.2-58.4Wo5.6-23.4, Fe/Mn=55±5, n=17), Augite (Fs22.4±8.0Wo35.2±5.7, range Fs11.4-36.0Wo27.2-44.8, Fe/Mn=51±8, n=7), Calcic Plagioclase (An96.5±0.7, range An94.9-97.7, n=45); Ferroan anorthosite clasts (Mg#=64.2±2.1, An96.7±0.3, n=3), Magnesian-suite anorthosite clast (Mg#=80.8, An95.9, n=1), Hyper-ferroan clasts (Mg#=37.4±5.8, An96.8±0.7, n=2).
Classification: Lunar (feldspathic fragmental breccia)
Specimens: Cascadia holds 149.8 g (main mass) in two pieces, in addition to 1 polished thin section; 11.6 g at UAb.
I have not studied Northwest Africa 14657. It may be another pair of the NWA 8046 clan.
Meteoritical Bulletin Database
Gross J., Treiman A. H. and Mercer C. N. (2014) Lunar feldspathic meteorites: Constraints on the geology of the lunar highlands, and the origin of the lunar crust. Earth and Planetary Science Letters 388, 318–328. (link)