74275 is a fine-grained, vesicular high-Ti mare basalt with significant armalcolite content. It contains groundmass plagioclase, pyroxene and ilmenite with larger crystals of pink pyroxene (up to 0.5 mm) and olivine (up to 0.7 mm) and laths of armalcolite rimmed with ilmenite (up to 0.7 mm in length). Pyroxene rims are present on some olivine phenocrysts. Minor blebs of metallic iron and troilite are found in the groundmass. Olivine megacrysts, some termed “dunite inclusions”, are common. Small euhedral chromite crystals are found as inclusions in the olivine clusters.
The sample weighed 1493 grams before analysis and has been dated at 3.85±0.08 billion years (Rb/Sr).
Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/
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.