Moon rocks(lunar rocks) Samples of the Moon returned by Apollo and Luna spacecraft. Lunar soils, or fines, consist of glasses, aggregates, and meteorite debris in addition to recognizable fragments of larger rock types. Hand specimens include mare basalts (low titanium content from the western maria, high titanium content from the eastern maria, and aluminous basalts from Mare Fecunditatis), non-mare basalt (also known as KREEP because of its high content of potassium (symbol K), rare earth elements, and phosphorus (symbol P)), and anorthositic rocks from the highlands. Rare lunar-rock types include granite, ultramafic green glass, pyroxenite, norite, troctolite, and dunite. Most highland rocks have been impact metamorphosed (to produce cataclastic, recrystallized, and impact melt textures), but cumulates are also observed and these date back to the formation of the first lunar crust.
Lunar rocks are depleted in volatile and siderophile elements. Strong correlations exist between elements that are geochemically similar to one another (e.g. iron and manganese) or that are both excluded by major minerals (e.g. potassium and lanthanum). The major lunar minerals are calcic plagioclase, clino- and ortho-pyroxene, olivine, and ilmenite. Minor phases include spinels, K-feldspar, troilite, metallic iron, quartz, tridymite, cristobalite, apatite, and whitlockite. Uniquely lunar minerals include armalcolite, tranquillityite, and pyroxferroite. No hydrated phases, highly oxidized minerals, diamonds, or mineralization have yet been found.