Copper is an element of group 11, of period 4, an element of the
chalcophil transition metal block.
In the periodic table of the elements, copper is of the same family as silver
and gold, because each one has an orbital s occupied by a single electron on
fully filled p and d sublayers, which allows the formation of metallic bonds
(electronic configuration Ar 3d10 4s1). The three metals of this ＾copper group￣
have a character of nobility and increased rarity, from semi-noble copper to
genuinely noble gold, the first character being explained by their weak atomic
radii and their atomic stacking compactities. , their higher ionization
potentials due to the d sublayers, their relatively high melting points and
their low reactivities or relative chemical inertias8.
Naturally present in the earth's crust, copper in low doses is essential for the
development of any form of life. It is mainly used by humans in the form of
metal. Pure copper is one of the only metals colored with gold and osmium9. It
has a salmon pink hue or metallic shine on its fresh surfaces: this "red metal"
appreciated in goldsmithery and jewelry, for example as a support for enameled
pieces or rare enamels, was dedicated to the goddess of beauty Aphrodite and the
artists . It is sometimes referred to as red copper as opposed to brass (copper
and zinc alloys) improperly named "yellow copper". Ductile metal, it has
particularly high electrical and thermal conductivities which give it various
uses. It is also used as a building material and is used in the composition of
many alloys, cupro-alloys.
Copper, today a common metal, is the oldest metal used by humans10. The melting
point is not too high, the ease of reduction of copper oxide, often by a simple
wood fire, is remarkable.
Copper has 29 known isotopes, with mass numbers ranging from 52 to 80, as well
as seven nuclear isomers. Among these isotopes, two are stable, 63Cu and 65Cu,
and constitute all of natural copper in a proportion of approximately 70/30.
They both have a nuclear spin of 3/214. The standard atomic mass of copper is
63.546 (3) u.
The other 27 isotopes are radioactive and are only produced artificially. The
most stable of the radioisotopes among them is 67Cu with a half-life of 61.83
hours. The least stable is 54Cu with a half-life of around 75 ns. Most of the
rest have a half-life of less than one minute.
Occurrences in natural environments, mineralogy and geology, deposits and
deposits
Copper is an element sometimes abundant in some mining sites. The clarke amounts
to 55 to 70 g per tonne15.
Copper is one of the few metals that exists in its native state under cubic mesh
crystals. Well-formed crystals are rare, but often dentritic threads, leaf
assemblies or more or less massive impregnation overlays can be common in the
rare sites, where it can be observed. There the Neolithic men had access to this
easy to shape material, by hammering it lightly, native copper is among the
first metal used by men. The occurrence of native copper is however quite low.
Azurite and malachite crystals on native copper
The copper element, because of its chalcophilic nature or its attraction for the
sulfur element S, appears most frequently in the form of sulfide or sulfo-salt.
It was found in significant quantities on the island of Cyprus nicknamed the
island of a thousand mines16. The sulphide minerals like chalcopyrite (CuFeS2),
bornite (Cu5FeS4), cubanite (CuFe2S3) and especially covellin (CuS) and
chalcosine (Cu2S) are interesting sources of copper, as well as its carbonates:
azurite (Cu3 (CO3 ) 2 (OH) 2) and malachite (Cu2CO3 (OH) 2) and one of its
oxides: cuprite (Cu2O) 17.
The minerals containing the copper element often have a beautiful colored
appearance, like the Eilat stone.
copper aluminum lead Zinc tin nickel iron
magnesium bismuth manganese chromium cobalt titanium