Lunar Ultramafic Glasses, Chondrules and Rocks

Abstract

Analysis of all samples returned by lunar missions before Apollo 15 has shown green glasses of ultramafic composition in soil and/or microbreccia samples1–7. Ultramafic glasses in Apollos 11 and 14 and Luna 16 samples are rare and similar to each other in composition but different from any of the rocks collected at these sites. Ultramafic glasses in the Apollo 12 samples are also low in abundance and while they are generally similar to the ultramafic glasses collected on other missions, they have consistently higher TiO2 contents (Table 1), thus closely resembling ultramafic rocks collected at the same site (for example, 12036, 12040). This report gives details of our work on Apollo 15 ultramafic green glasses and discusses likely origins of all green glasses.