DARWIN 101, Five Glimpses of His Life and Work

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Geology 101 with Willsey, Episode #1: Intro to Earth

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Geology 101 with Willsey, Episode #2: Intro to Plate Tectonics

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Geology 101 with Willsey, Episode #9: Igneous Rocks, Part One

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Geology 101: Natural Processes that Form Colored Gemstones | GIA Knowledge Sessions Webinar Series

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Gold Geology 101: How to Find High-Grade Gold Deposits

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