Fact sheet
15485 (and 15486) are samples of vitrophyric pigeonite basalt, a rapidly cooled variety of quartz-normative basalt found to be rather common at the Apollo 15 site. They are very vesicular with porphyritic, diktytaxitic texture. The porphyritic clinopyroxene vitrophyre is composed of elongate pyroxene prisms in a matrix of opaque devitrified glass with 3% globulose vugs. Pyroxene crystals are highly zoned. The main accessory minerals are ilmenite, troilite and metallic iron.
The sample weighed 104.9 grams before analysis. The boulder from which 15485 was collected has been dated at 3.4 b.y.
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 colourful dendrites around the thin section.
The Apollo 15 landing site was in the Apennine Highlands, and close to Hadley Rille — a long, narrow winding valley. Approximately 76 kg of lunar material, including soil, rock, core-tube and deep-core samples, were returned to Earth.
This mission was the first flight of the Lunar Roving Vehicle which allowed the astronauts to venture further from the Lunar Module than in previous missions. During three periods of extravehicular activity, or EVA, on July 31st, and August 1st and 2nd, Scott and Irwin completed a record 18 hours, 37 minutes of exploration, travelling 17.5 miles, in the first car that humans had ever driven on the Moon.
Apollo 15 was launched on 26 July 1971.
