S5003140

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Fig. 10 Furnace erected ln Central Iran for lead smelting experiments (After Pleiner 1967)

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Fig. 11 Furnace used for tin smelting experlment8 ln South Afrlca (After Friede & Steel 1976)

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DETERM1NATIVE MINERALOGY AND THE ORIG1NS OP METALLURGY

J A Charles

Department of Metallurgy and Materiale Science, Unlveralty of Cambridge, Pembroke Street, Cambridge

Abatract

The lmportant determlnatlve features of the minerale of lead, copper, arsenie, tin and Iron are considered ln relatlon to the early development of metallurgy, both ln the context of lnltlally accldental alloying development and then ln the purposeful selection of addltlons as effects and causes were identifled. Explanatlons are suggested for the transitlon from copper to copper-arsenlc alloys and then to bronze. The productlon of Iron durlng the Bronze Age and lts eventual domlnance will be considered, the latter partlcularly as a functlon of the ablllty to produce equivalent properties by carburisatlon.

Keywords:    MINERALS, COPPER, COPPER-ARSENIC, BRONZE,

LEAD, IRON, METALLURGY

Introductlon

Flrstly, an apology for the broad generalisatlons and slmpllficatlons ln what I am about to say and for presentlng what ls a very long story, ln the sense of real time, as lf lt were a smooth and rapld seąuential process occurrlng unlformly throughout the world unaffected by anthropologlcal consideratlons. Nothlng could be further from archaeological hlstory. The development of metal usage and the introductlon and use of particular metale and alloys was very heterogeneous both ln location and time. Much depended on the availa-bllity of raw materiale and, I believe, on the social structure and the status of the smith ln that social structure. What I believe one can do, however, ls to put together a composlte metallurgical plcture which assumes the best possible conditlons for lnnovatlon and experlment and for the pravious tradl-tions to be available, either maintalned wlthln one aociety or dlffused from another society by travel, trade or war wlth lts attendant occupatlona and movements.

What 1 seek to do ls to give a sense of the basls for metal dlscovery from generał archaeological knowledge and how the recognltlon of minerale and thelr connection to smelted products would be established. Puttlng ourselvea ln the positlon of a late Neolit hic man, we have become very 'earth-consclous' We are cultivating the soli now, but wearestlll stone-gJtherers always looking for good stones for toola or for building purposes, or Just clearing them away from our cultlvation plots. At such a time coloured minerale are much morę widely abundant on the surface and at outcrop6 where mineralizatlon exlsts than they are today, and such materlals attract our attention not only for thelr colour but also for thelr structure and texture. By frequent handllng (as any mineralogy student knows), expected welght ln relatlon to slze (l.e.