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South American metal working seems to have developed in the Andean region of modern Peru, Bolivia, Ecuador, Chile, and Argentina with gold and native copper being hammered and shaped into intricate objects, particularly ornaments. [1] [5] Recent finds date the earliest gold work to 2155–1936 BC. [1] and the earliest copper work to 1432–1132 BC.
Metallurgists throughout medieval Europe were generally free to move within different regions. For instance, German metallurgists in search of rich precious metal ores took the lead in mining and influenced the course of metal production, not only in East and South Germany but also in almost all of Central Europe and the Eastern Alps.
From a combined iron and steel production of 203 million tons in 1979, US output fell almost in half, to 107 million tons in 1982. Some steel companies declared bankruptcy, and many permanently closed steelmaking plants. By 1989, US combined iron and steel production recovered to 142 million tons, a much lower level than in the 1960s and 1970s.
There was no fundamental change in the technology of iron production in Europe for many centuries. European metal workers continued to produce iron in bloomeries. However, the Medieval period brought two developments—the use of water power in the bloomery process in various places (outlined above), and the first European production in cast iron.
Find out which American Companies have been around the longest. From John Deere and Jack Daniel's to Coca-Coal and Carhartt, these are some of the oldest companies in America, some of which are ...
Pages in category "Metal companies of the United States" The following 44 pages are in this category, out of 44 total. This list may not reflect recent changes .
Steel is an alloy composed of between 0.2 and 2.0 percent carbon, with the balance being iron. From prehistory through the creation of the blast furnace, iron was produced from iron ore as wrought iron, 99.82–100 percent Fe, and the process of making steel involved adding carbon to iron, usually in a serendipitous manner, in the forge, or via the cementation process.
A saltpetre works or nitrary [1] is a place of production of potassium nitrate or saltpetre used primarily for the manufacture of gunpowder. The saltpeter occurs naturally in certain places like the "Caves of Salnitre" ( Collbató ) known since the Neolithic.