60618 is a rake sample collected close to the Lunar Module. It contains large plagioclase crystals in a grey matrix with prominent vesicles. On first impression it appears to be a porphyritic basalt but it is actually composed of two lithologies anorthosite and impact-melt rock. The impact-melt rock portion contains many relatively large equant (0.5 mm) plagioclase grains (which are relicts) and plagioclase needles (up to 0.5 mm) which crystallized from the melt. Irregular olivine and pyroxene subophitically enclose the plagioclase. Minor phases include ilmenite, armalcolite, metallic iron, schreibersite and troilite (difficult to see in our thin section).
Our thin section image shows a sequence of numbers (1-6) that have been scribed on the glass behind the six rock fragments.
The sample weighed 21.7 grams before analysis and has not been dated.
Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/
The Apollo 16 landing site was in the hilly region around Descartes crater in the lunar highlands. The landing spot was chosen to allow the astronauts to gather geologically older lunar material (Descartes Formation and the Cayley Formation) than the samples obtained in the first four landings, which were in or near lunar maria.
The mission lasted 11.1 days, with a stay on the lunar surface of 71 hours. The crew were on the lunar surface for 20.2 hours during which they traversed approximately 27 kilometers and collected approximately 96 kilograms of samples.
Apollo 16 was launched on 16 April 1972.