Social Science (087) — AI-generated practice question

In igneous and metamorphic rocks, metallic minerals occur in cracks, crevices, faults, or joints. They are formed when minerals in liquid/molten and gaseous forms are forced upward through cavities towards the Earth's surface. As they rise, they cool and solidify, depositing minerals in these cracks. Smaller occurrences are called veins and larger ones are called lodes. Major metallic minerals like tin, copper, zinc, and lead are obtained from veins and lodes.

Source: Chapter 5 – Minerals and Energy Resources, Mode of Occurrence of Minerals

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• The examiner expects three clear points: (1) location — cracks/crevices/faults/joints, (2) process — molten/gaseous material forced upward, cools and solidifies, (3) terminology — veins and lodes with examples.
• Always name at least two metallic minerals (tin, copper, zinc, lead) as examples — this fetches the application mark.
• Do not mix up igneous/metamorphic mode with sedimentary (beds/layers) or placer deposits — a common error.