|78597 is a vuggy, medium-grained high-Ti basalt that was collected as part of a rake sample. It is an olivine-microporphyritic ilmenite basalt with large olivine grains (rotation 1) mantled by pyroxene and set in a predominantly variolitic groundmass. Plagioclase laths in the groundmass have hollow cores (interfasciculate) and are bundled in sheaths with intergrown pyroxene. Ilmenite occurs in chains. Minor silica and a trace of tranquillityite have also been reported.
The sample weighed 319 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.