71577 and 71578 are olivine-microporphyritic ilmenite basalts - similar to 71569. Both were collected as rake samples. They are fine-grained, ilmenite-rich basalts with minor vugs and vesicles. The groundmass is variolitic with bow-tie intergrowths of plagioclase and pyroxene. Olivine is skeletal, often partially resorbed. It contains melt inclusions (rotations 1 & 2). Ilmenite is irregular is shape, often acicular, and penetrating other minerals. Armalcolite and metallic iron are also reported.
The sample weighed 353.9 grams before analysis and has not been dated.
Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/
The mounting resin of this thin section has deteriorated over time and now contains clusters of feathery crystallites.
Apollo 17, the final manned landing mission, had two objectives: to obtain samples of ancient rocks from the lunar highlands and to look for evidence of younger volcanic activity on the valley floor.
This small Collection contains material deriving from both periods, including igneous rocks around 4.3 billion years old from the lunar highlands as well as younger volcanic samples dating from about 3.6 billion years ago.
Apollo 17 was launched on 7 December 1972.