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A lunar basalt (Apollo 11 sample 10062)

A lunar basalt (Apollo 11 sample 10062)
A lunar basalt (Apollo 11 sample 10062) Color photograph of Apollo 11 Sample 10062. The ruler is marked in centimeters. The rock is a high-titanium basalt, and very old, 3.8 billion years old, dating to the time of the Late Heavy Bombardment. NASA

According to the Lunar Sample Compendium, Apollo 11 sample 10062 is "an old, low-K, high-Ti basalt from Apollo 11. Based on texture and composition, James and Wright (1972) termed 10062 an ophitic ilmenite basalt, whereas Gamble et al. (1978) describe the texture as subophitic (figure 1).  At 3.8 b.y., basalt 10062 is one of the oldest lunar mare basalts (other than those found as clasts in breccias).  It has been exposed to cosmic rays for 90 m.y. (the apparent age of West Crater)."

"The texture is ophitic, with radiating lath-like and acicular crystals of plagioclase, intergrown with tabular and skeletal crystals of ilmenite, irregular grains of zoned clinopyroxene and olivine (figure 2).  Late stage silica, fayalite, ulvöspinel, troilite and apatite are present in the mesostasis. The abundance of ilmenite is striking, with some grains as large as ~ 1 mm.  Some ilmenite has relict cores of armalcolite, which appears to have been replaced and overgrown by ilmenite."