Studies of exsolution lamellae in lunar pyroxenes, in particular in clinopyroxenes, augite and pigeonite, demonstrated that these minerals had been created during reaction at temperatures lower than their melting point. These same studies proved that lunar pyroxenes cooled slowly after their formation. From those measurement it have been estimated that a basalt flow 6 meters thick located on Apollo 15 landing site cooled at 0.2 to 1.5 degree per hour. Rare observations were also made revealing, inside lunar pyroxene crystals, of shock lamellae formed long ago at the time of severe meteoritic impacting. In crystalline rocks such as anorthosites, the chemical composition of pyroxenes indicates a higher content for magnesium than for iron.
Plagioclase feldspars Most of lunar feldspars belong to the plagioclases family.
The plagioclases feldspars are major constituents of rocks constituting the lunar crust. Statistically, lunar plagioclases have a lower sodium content and thus are closer to the pole anorthite than those found on Earth. Olivines Olivine is one of the major constituents of rocks forming the lunar crust. The main impurities of lunar olivines are calcium, manganese, chromium and aluminium. In the same manner, one can note abnormally high chromium content inside the pyroxenes crystals of the same basalts.