Classification
Moon rocks fall into two main categories, the ones found in the lunar highlands (terrae) or the maria. The terrae consist dominantly of mafic plutonic rocks. Regolith breccias with similar protoliths are also common. Mare basalts come in three distinct series in direct relation to their chemistry: high-Ti basalts, low-Ti basalts, and Very Low-Ti (VLT) basalts.
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