Northwest Africa 12869: Primitive Achondrite from the CR2 Parent Body or Member of a New Meteorite Group?

C. B. Agee, H. Aikin, K. Ziegler

51st Lunar and Planetary Science Conference (2020), Abstract #2292


“We report here the classification of a new primitive achondrite, Northwest Africa (NWA) 12869, which is a plagioclase-bearing harzburgite with oxygen isotopes similar to CR2 chondrites, however the high Fa- and Fs-content and Fe/Mn of its olivines and pyroxenes appear to be inconsistent with a direct genetic link to CR2. Instead, NWA 12869 shows petrologic and geochemical resemblance to about a dozen other primitive achondrites or highly recrystallized chondrites which have been linked to the CR2 parent body because of similar oxygen and chromium isotopes [1,2]. An alternative interpretation is that these meteorites are not derived from the CR2 parent body, but instead represent a separate new meteorite group.”