Also around 3000 B.C.E. , it was discovered that mixing copper, known from about 3500 B.C.E. , with tin would create a much harder metal known as bronze. | Although copper had been known since 3500 B.C.E. in Mesopotamia, the discovery of bronze did not occur until around 3000 B.C.E. | Another major development around 3000 B.C.E. was the discovery that copper could be mixed with a much harder metal known as tin. | The development of bronze by mixing copper and tin probably occurred around 3000 B.C.E. but may have happened as early as 3500 B.C.E. |
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