This 1.4 million-year-old hand axe was chipped off a hippo femur

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By Diego Delso, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=74486418
Hand axes are fairly common finds at sites dating between 2 million and 1 million years old. These sturdy tools have two sides (also called faces) and a shar…