Metals have been widely used in Japan since the Yayoi period (about 300 BC - AD 300), when bronze and iron were introduced from Han Dynasty China. Iron was used to make tools and weapons. With the introduction of millet and rice growing in paddy fields, a more settled way of life had developed, but wars over land boundaries required weapons and armour. Bronze was reserved for the production of religious ritual objects such as mirrors, daggers, spears, halberds and the tall straight-walled bells called dōtaku.
The Kofun period (about AD 300-7th century) saw great technological advances. Japan had plentiful supplies of copper, and gold was discovered in 749. The mercury amalgam method was used to gild copper plate used to decorate horse trappings. The making of weaponry and armour, especially swords, developed into a highly-skilled and respected craft over the following centuries. materials, such as shakudō were widely used for decoration.
Buddhism was the dominant influence in the arts of the mid-sixth to tenth centuries. Bronze sculptures in the Chinese tradition were the norm, such as the famous Great Buddha of the Tōdaiji Temple in Nara (eighth century). They were made by the lost-wax technique. Bronze was gradually replaced by wood, though smaller bronze pieces were still made throughout the medieval period and into the Edo period (1600-1868).
Meanwhile, bronze was still widely used for secular objects, such as mirrors, and, from the Meiji era (1868-1912), impressive ornamental vases and other ornaments. Swordsmiths and armourers adapted their ironworking skills, making articulated animal ornaments and even ornate flower vases.