71546 is an olivine-poor ilmenite basalt with a variable texture from fine-grained variolitic areas to coarser granular areas that was collected in a rake sample. Pyroxene forms the largest grains and encloses ilmenite and plagioclase feldspar (rotation 1).
The sample weighed 150.7 grams before analysis and has not been dated.
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.