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The conservation and restoration of copper and copper-alloy objects is the preservation and protection of objects of historical and personal value made from copper or copper alloy. When applied to items of cultural heritage , this activity is generally undertaken by a conservator-restorer .
Armstrong was founded in 1890 as the Armstrong Bros. Tool Company in Chicago, Illinois by the five Armstrong brothers. The brothers manufactured bicycle parts and tools for repairing and manufacturing bicycles from the brothers' backyard shed and managed a retail store in downtown Chicago.
A second factory was opened in Buffalo, New York in 1914, now the site of General Motors' Tonawanda Engine plant. [4] The company was acquired by Snap-on in 1993. [citation needed] In 2011 it was officially renamed Snap-on Industrial Brands. [5]
Sican tumi, or ceremonial knife, Peru, 850–1500 CE. Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century.
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
An alloy is distinct from an impure metal in that, with an alloy, the added elements are well controlled to produce desirable properties, while impure metals such as wrought iron are less controlled, but are often considered useful. Alloys are made by mixing two or more elements, at least one of which is a metal.
Although two definite major alloying compositions for the production of MBII copper-based artifacts, (1)copper with arsenic and (2) copper with tin, are detected, to date no visible connection of specific alloy with specific type of object or different periods has been seen: both alloys appear in similar objects and in burials dated to the ...
Copper bells, axe heads and ornaments from various parts of Chiapas (1200–1500) on display at the Regional Museum in Tuxtla Gutierrez, Chiapas.. The emergence of metallurgy in pre-Columbian Mesoamerica occurred relatively late in the region's history, with distinctive works of metal apparent in West Mexico by roughly 800 CE, and perhaps as early as 600 CE. [1]