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The first published picture of a hand axe, drawn by John Frere in the year 1800. Flint hand axe found in Winchester. A hand axe (or handaxe or Acheulean hand axe) is a prehistoric stone tool with two faces that is the longest-used tool in human history. [1]
Calx – calcium oxide; was also used to refer to other metal oxides. Chalcanthum – the residue produced by strongly roasting blue vitriol (copper sulfate); it is composed mostly of cupric oxide. Chalk – a rock composed of porous biogenic calcium carbonate. CaCO 3; Chrome green – chromic oxide and cobalt oxide.
A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. [1] In numismatics , coins often derived their value from the precious metal content; however, base metals have also been used in coins in the past and today.
Metal: The use of any metallic tool is rather strange and extraordinary. It seems that the copper was not used for the miners' tools. However copper chisels and discarded axes could be utilized as wedges. [16] Other evidence: The presence of coal and charcoal, crucial for the firing (fire-setting) and furnace (fuel), is habitual. Leather sacks ...
Copper(II) sulfate forms a blue crystalline pentahydrate, the most familiar copper compound in the laboratory. It is used in a fungicide called the Bordeaux mixture. [3] Ball-and-stick model of the complex [Cu(NH 3) 4 (H 2 O) 2] 2+, illustrating the octahedral coordination geometry common for copper(II).
Latten is a further term, mostly used for coins with a very high copper content. Today the term copper alloy tends to be substituted for all of these, especially by museums. [1] Copper deposits are abundant in most parts of the world (globally 70 parts per million), and it has therefore always been a relatively cheap metal.
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Tetrahedrite is a copper antimony sulfosalt mineral with formula: (Cu,Fe) 12 Sb 4 S 13. It is the antimony endmember of the continuous solid solution series with arsenic-bearing tennantite. Pure endmembers of the series are seldom if ever seen in nature. Of the two, the antimony rich phase is more common.