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8.1 Introduction

Copper, the red metal, apart from gold theonly metallic element with a color differentfrom a gray tone, has been known since theearly days of the human race. It has always

been one of the significant materials, and to-day it is the most frequently used heay non-ferrous metal. !he utility of pure copper is

based on its physical and chemical properties,aboe all, its electrical and thermal conductiity"e#ceeded only by siler$, its outstandingductility and thus e#cellent workability, andits corrosion resistance "a chemical behaiormaking it a half-noble metal$.

Its common alloys, particularly brass andbron%e, are of great practical importance. Cop-per comp ound s ores are dist ingu ishe d bybright coloration, especially reds, greens, andblues. Copper in soil is an essential trace ele-ment for most creatures, including humans.

&tymology. 'ccording to mythology, the god-

dess (enus "or 'phrodite$ was born on the)editerranean island of Cyprus, formerly*urrpoc "+reek$, where copper was e#ploitedmillennia before Christ. !herefore, in earlytimes the omans named it cyprium, latercalled cuprum. !his name is the origin of cop-

per and of the corresponding words in mostomance and +ermanic languages, e.g., cobre"panish and ortuguese$, cuire "/rench$,*upfer "+erman$, koper "0utch$, and koppar"wedish$.

' 1cross with handle1, from the &gyptianepoch, was called the mirror of (enus. In thealchemistic period, this sign meant the metalcopper. &en now in astronomy it designatesthe planet (enus and in biology stands for 1fe-

male1.

istory 32-245. !he first metals found by6eolithic man were gold a nd copper, later sil-er and meteoric iron. !he earliest findings ofcopper are presumed to be nearly nine millen-nia old and came from the region near *onyain southern 'natolia "!urkey$. 7ntil recentlythe si#-millennia-old copper implementsfrom Iran "!ele iallc$ were presumed to be the

Handbook of Extractive Metallurgy

oldest. In the 8ld orld, copper has beenworked and used since appro#imately:;

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Handbook of Extra ctive Metallurgy

ninesyntheticradioacti eisotopeswithatomicmasses

bet ween

@9 and?B, of which?;Cu hasthelongesthalf-life,ca. @B.@h.

Crystaltructure. 'tmoderate

pre ssu re

s,coppercrystalli%es fromlowtemperatures upto itsmelting

point ina cubic-closest-

packed"ccp$lattice,

type 'l"also /

or Cu$with thecoordinationnumber2. J-raystructureanalysis

yiGa)i't't

D!hCoCaC

a!h!h t,

s ol id co e r 2?

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nce of recrystalli%ationtemperaturean dgrains i%e ontheduration ofheatingtheamountof

preious colddeformation andthedegreeof

purityofcoppercan bedeterminedfromdiagram

s. !h erecrystalli%ationtemperature i sca. 4?->;5. 'n e#actknowledge of the behaior of solid andliquid copper toward gases is importantfor production and use of the metal.ith the e#ception of hydrogen, thesolubility of gases in molten copperfollows enryPs law: the solubility is

proportional to the partial pressure.

8#ygen dissoles in molten copperas coppe r"$ o#ide up to aconcent ration of 2 .?@ Cu2