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Metallurgy in China has a long history, with the earliest metal objects in China dating back to around 3,000 BCE. The majority of early metal items found in China come from the North-Western Region (mainly Gansu and Qinghai, 青海). China was the earliest civilization to use the blast furnace and produce cast iron. [1]
One of the fragments was made of bloomery iron rather than meteoritic iron. [37] [38] The earliest iron artifacts made from bloomeries in China date to end of the 9th century BC. [39] Cast iron was used in ancient China for warfare, agriculture and architecture. [9] Around 500 BC, metalworkers in the southern state of Wu achieved a temperature ...
The first elemental metal with a clearly identifiable discoverer is cobalt, discovered in 1735 by Georg Brandt, by which time the Scientific Revolution was in full swing. [6] Even then, cobalt might have been prepared before the 13th century by alchemists roasting and reducing its ore, but, in any case, its distinct nature was not recognised ...
Although, the advantages of copper were many, the material was too soft to find large scale usefulness. Through experimentation or by chance, additions to copper lead to increased hardness of a new metal alloy, called bronze. [3] Bronze was originally composed of copper and arsenic, forming arsenic bronze. [4]
Although earlier temporary pontoon bridges had been made in China, the first secure and permanent ones (and linked with iron chains) in China came first during the Qin dynasty (221 BC–207 BC). The later Song dynasty (960–1279 AD) Chinese statesman Cao Cheng once wrote a description of the early pontoon bridges in China. [386]
Overall, the U.S. trade deficit of all goods and services fell last year by almost 19%, the largest drop since 2009, as Americans bought less foreign oil and fewer China-made phones, toys and ...
World tin production, 1946. During the Middle Ages, and again in the early 19th century, Cornwall was the major tin producer. This changed after large amounts of tin were found in the Bolivian tin belt and the east Asian tin belt, stretching from China through Thailand and Laos to Malaya and Indonesia.
John King knew his small town of Rockdale, Texas, had landed on the global crypto map when three Chinese bitcoin miners showed up at City Hall unannounced this summer. Bitcoin mining crackdown in ...