Hồng Bàng dynasty
Bronze tools

By about 1200 BC, the development of wet-rice cultivation and bronze casting in the Mã River and Red River plains led to the development of the Đông Sơn culture, notable for its elaborate bronze drums. The bronze weapons, tools, and drums of Đông Sơn sites show a Southeast Asian influence that indicates an indigenous origin for the bronze-casting technology. Many small, ancient copper mine sites have been found in northern Vietnam. Some of the similarities between the Đông Sơn sites and other Southeast Asian sites include the presence of boat-shaped coffins and burial jars, stilt dwellings, and evidence of the customs of betel-nut-chewing and teeth-blackening.
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