The limestone axe is the oldest ever found in Europe. …
Gary Scott and Luis Gibert of the Berkeley Geochronology Centre in Berkeley, California applied a technique called magnetostratigraphy to determine that the hatchets were in fact crafted between 760,000 and 900,000 years ago. Magnetostratigraphy is based on the periodic reversal of Earth’s magnetic field.
Acting like tiny compasses, fine-grained magnetic minerals in the tools contain a record of the polarity at the time they were used. Once buried in sediment, the polarity is preserved.
“The age (of the axes) must be Early Pleistocene, the most recent period dominated by reverse polarity, 1.78 to 0.78 million years ago,” the researchers concluded. They published their findings in the British journal Nature.
via European hand axes nearly one million years old | COSMOS magazine.