INTORDUCTION TO ANCIENT METALLURGY

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1 INTORDUCTION TO ANCIENT METALLURGY ANCIENT METALS METAL SYMBOL MP O C BP O C DENSITY GOLD Au 1060 2970 19.3 SILVER Ag 961 2210 10.5 COPPER Cu 1083 2695 8.92 LEAD Pb 327 1725 11.3 ZINC Zn 420 906 7.

1 1 INTORDUCTION TO ANCIENT METALLURGY ANCIENT METALS METAL SYMBOL MP O C BP O C DENSITY GOLD Au SILVER Ag COPPER Cu LEAD Pb ZINC Zn TIN Sn IRON Fe STUDY OF ANCIENT METALLURGY Formation of minerals Exploitation of minerals in antiquity Development of metallurgy Metal trade Impact of metal and metal trade on social, economic and military history

2 2 STAGES FROM ORE TO FINISHED METAL OBJECT ORE SOURCE MINING THE CASTING HOT AND COLD WORKING FINISHED OBJECT ORES AND STONES REFINING AND CASTING ORE DRESSING INGOT GONGUE ORE SMELTING SLAG Significant properties of metallurgy to ancient metal smiths Color: (determined value) Luster: (determined value) Acoustics: (copper gongs, bells) Casting ability: (mass production) Hardness: (tool and weapons) Strength and malleability: (tools and weapons) Welding and soldering: (flexibility in construction) Recycling: (remelting) STAGES IN THE DEVELOPMENT OF METALLURGY Date BC First use of native copper 9500 First evidence for the extraction of metal (Pb) 6000 Lead glazing 5000 First copper object made by casting 5000 First alloys (Cu-As) 4500 First bronze (Cu-Sn alloy) 3200 First iron implements (meteoric) 2500 First evidence for iron smelting 1700 Full use of steel (carburizing & quenching) 800 DIFFUSION OF COPPER METALLURGY IN THE OLD WORLD BRITISH ISLES IBERIA CENTRAL EUROPE AEGEAN TROY EGYPT SKANDI- NAVIA ANATOLIA PALESTINE TRANS- CAUCASIA IRAN MESOPO- TAMIA CHINA INDIA

3 DISTRIBUTION OF SOME METALS IN EARTH S CRUST* FORMATION OF SECONDARY ORES Cu Ag Au Pb Sn Surface Rocks 25 0.15 0.01 15 3.6 Continents 82 0.2 0.03 12 2.0 Basement rocks 120 0.

3 3 DISTRIBUTION OF SOME METALS IN EARTH S CRUST* FORMATION OF SECONDARY ORES Cu Ag Au Pb Sn Surface Rocks Continents Basement rocks In ppm DEVELOPMENT OF MINING Neolithic Age (>3500 BC): Quarries, open workings, sloping shafts, gradual galleries Early Bronze Age ( BC): Stripping of outcrops, shafts with staircases Middle and Late Bronze Age ( BC): Timbering of shafts, drainage, wider galleries. Iron Age (1st millennium BC): Drainage exits, large quarries, transportation, ventilation FIRE SETTING

4 4 ORE DRESSING METAL CYCLE Ore dressing is the treatment of ores and mineral products by mechanical, physical or chemical means to separate the valuable minerals from the worthless constituents to increase its concentration Smelting Metal Ore Corrosion Metal Artifacts Production SMELTING REQUIREMENTS A furnace that can reach high enough temperatures where metals will melt. Supply of heat at a sufficient rate to maintain temperatures and conduct the smelting and slag forming reactions. Generate a reducing gas that can decompose the metal oxides disseminated in the ore COMBUSTION OF CARBON 2C + O 2 2CO CO 2 C + O 2 C + CO 2 2CO

Conversion of CO 2 back to CO C + CO 2 2CO ANCIENT SHAFT FURNACE USE OF BLOW PIPES IN

5 5 REDUCTION OF METAL OXIDES BY CARBON MONOXIDE 1. Reduction of metal ore with CO MO + CO M + CO 2 2. Conversion of CO 2 back to CO C + CO 2 2CO ANCIENT SHAFT FURNACE USE OF BLOW PIPES IN ANCIENT SMELTING FURNACES TYPES OF BELLOW Human lungs can produce intermitent flow of 40l/min and l/min on continuous basis. This can heat a small area over 1000 o C.

6 6 OPERATION OF POT BELLOW IONIC COMPOUNDS vs METALS GRAIN STRUCTURE IN METALS Vacancy Grain Grain Boundary EFFECTS OF TEMPERATURE ON GRAIN STRUCTGUE AND MECHANICL PROPERTIES OF METALS

7 ALLOYS HOW CAN THE ATOMS OF TWO DIFFERENT METALS CAN MIX? Alloys are metallic substances that contain at least two elements. The base element in an alloy is a metal.

7 7 ALLOYS HOW CAN THE ATOMS OF TWO DIFFERENT METALS CAN MIX? Alloys are metallic substances that contain at least two elements. The base element in an alloy is a metal. The minor component of an alloy distribute in the base metal in two ways: a) They may occupy the spaces between the base metal b)they may substitute for base metal atoms. Solid solution Solid mixture ALLOY vs PURE METAL HARDNESS OF Cu- As ALLOYS

8 EARLIEST METAL OBJECTS Location Object Date (BC) Technique Aşıklı Cu beads 9000

Höyük Cu,Pb beads 6000 Annealing Cu slag Smelting Yarım Tepe I Pb bracelet 5700

BELT OF NEAREAST SITES OF EARLY NATIVE METALS AŞIKLI HÖYÜK METAL BEADS 1:Can Hasan,

8 8 EARLIEST METAL OBJECTS Location Object Date (BC) Technique Aşıklı Cu beads 9000 Cold work Zawi Chemi Cu beads 8500 Cold work Cayonu Cu pins 7000 Cold work Çatal Höyük Cu,Pb beads 6000 Annealing Cu slag Smelting Yarım Tepe I Pb bracelet 5700 Smelting Can Hasan Cu Mace 6000 Cold work Mersin Cu pin, axe 5000 Casting COPPER BELT OF NEAREAST SITES OF EARLY NATIVE METALS AŞIKLI HÖYÜK METAL BEADS 1:Can Hasan, 2:Asikli hoyuk, 3: Catal Hoyuk, 4. Hacilar, 5: Yumuk tepe, 6: Nevali Cori, 7: Cayonu, 8: Ramad,

9 9 CAN HASAN MACE HEAD COPPER SOURCES OF TURKEY SOME COPPER ORES COPPER INGOTS Azurite Chalcopyrite Chalcosite Tenantite Cuprite Malachite Uluburun Shipwreck (1350 BC) Rows of ox hide ingots. Bun ingot

10 CHALCOLITHIC CULTURES EARLY MESOPOTAMIAN

earliest copper smelting evidence in Anatolia.

corresponding to cultural interactions with

10 10 CHALCOLITHIC CULTURES EARLY MESOPOTAMIAN SITES This is the period that yielded the earliest copper smelting evidence in Anatolia. The period is divided into three roughly corresponding to cultural interactions with Mesopotamia: Early Chalcolithic (6th millennium BC) is also known as the Halaf Period. Middle Chalcolithic (5th millennium BC) is also known as the Obeid Period. Late Chalcolithic (4th millennium BC) is also known as the Uruk Period. URUK TRADE NETWORK HACINEBI TEPE

11 11 URUK EVIDENCE IN HACINEBİ METAL FINDS AT HACINEBİ An Uruk house Tokens in stamped container Beveled Rim Bowls (BRB) Wall cones (Uruk decoration) ARRIVAL OF CAUCASIAN CULTURES INTO EAST ANATOLIA MAJOR ELEMENTS ADDED TO COPPER FOR ALLOYING Evidence for the Caucasian cultures was recognized by the appearance of red burnished Karaz pottery. Cu-As Earliest copper alloy, accidental Cu-Sn Bronze, began to appear ~3000 BC Cu-Zn Brass, also known as orichalcum Cu-Sb Rare, mostly found in the Caucasus Cu-Pb Found mostly in cast copper objects (Highly used by the Romans)

12 Cu-As ALLOYS First Cu-As alloys appeared in the Near East in

Since Arsenic was not known in metallic form, it was believed

arsenic containing copper ores such as: Energite (3CuSAs 2 S 5 )

(CuFeS 2 ) Sometimes arsenic minerals orpiment (As 2 S 3 ) or

12 12 Cu-As ALLOYS First Cu-As alloys appeared in the Near East in the latter part of 4th Millennium BC. Since Arsenic was not known in metallic form, it was believed that these alloys were accidentally produced from smelting arsenic containing copper ores such as: Energite (3CuSAs 2 S 5 ) Tennantite (Cu 3 SAsS 3 ) Arsenopyrite (FeAsS) with chalcopyrite (CuFeS 2 ) Sometimes arsenic minerals orpiment (As 2 S 3 ) or realgar (AsS) were added to copper ore during smelting. NAHAL MISHMAR APPEARENCE OF Cu-As ALLOYS ARSLANTEPE

13 LOCATION OF İKİZTEPE İKİZTEPE METALS ARSENIC CONCENTRATION OF İKİZTEPE METALS ACCORDING TO PERIODS DISTRIBUTION OR ARSENIC CONCENTRATION IN

13 13 LOCATION OF İKİZTEPE İKİZTEPE METALS ARSENIC CONCENTRATION OF İKİZTEPE METALS ACCORDING TO PERIODS DISTRIBUTION OR ARSENIC CONCENTRATION IN İKİZTEPE OBJECTS % As Number of Samples LC EB I EB II EB III MB I 0 < >10 As %

14 ARSENIC SOURCES FOR İKİZTEPE METALURGISTS WHY Cu-As ALLOYS WERE ABANDONED Roasting of sulfide ores with arsenic caused arsenic to be lost as a sublimate Due to the volatility of arsenic, its

14 14 ARSENIC SOURCES FOR İKİZTEPE METALURGISTS WHY Cu-As ALLOYS WERE ABANDONED Roasting of sulfide ores with arsenic caused arsenic to be lost as a sublimate Due to the volatility of arsenic, its composition in copper could not be easily controlled. The availability of recognizable arsenic rich ores were limited Toxic effect of arsenic was detrimental to the health of the smith. HOW Cu-Sn ALLOY WAS RECOGNIZED? HARDNESS OF BRONZE Since stannite (Cu 2 SFeS.SnS 2 ) resembles arsenical copper ores, it could have been accidentally smelted and Cu-Sn bronze could be obtained. Insoluble cassiterite during natural oxidation and enrichment of primary ores will remain in the iron hat (gossan). If cassiterite containing gossan is used as flux in copper smelting, tin could be incorporated into copper.

15 15 PREPARATION OF Cu-Sn ALLOYS 1. Metallic copper and tin can be melted together at desired proportions. 2. Copper and tin ore cassiterite may be smelted together. 3. Cementation method can be used in which cassiterite is added to the surface of molten copper under charcoal in a furnace where the tin is reduced directly into the melt: SnO 2 + C Sn + CO 2 EARLIEST BRONZES OCCURANCE OF BRONZE BEFORE 22OO BC, OCCURANCE OF BRONZE AFTER 2200 BC

16 16 BRONZES OF ANATOLIA Figurines of Tell Atchana in the Amuq plain dated to around 3000 BC Bronzes of Troy II, dated to 2800 BC Bronzes of Alacahoyuk and Horoztepe dated to the 2nd half of 3rd millennium BC Bronze objects from the royal tombs at Ur Mesopotamia BC MAP OF SOUTH CENTRAL ANATOLIA AMUQ FIGURINES ALACAHÖYÜK EBA OBJECTS

17 17 ALACAHÖYÜK EBA METALS TROY Alacahöyük EBA Metals Number of Samples Cu As>1.0 Sn>2.0 As & Sn Esin 1967 TREAURES FROM UR

18 18 KESTEL MINE ENTRANCE TO KESTEL UNDERGROUND WORKINGS ORE DRESSING AT KESTEL ENTRANCE TO KESTEL MINE

19 19 KESTEL TIN MINE ( BC) FIRE SETTING PACKETS AT KESTEL C 14 DATE FOR KESTEL CHARCOAL KESTEL MINE PLAN

20 20 GÖLTEPE WORKSHOP GRINDING TOOLS AT GÖLTEPE

21 GÖLTEPE STORAGE VESSELS TIN METALLURGY AT GÖLTEPE

cassiterite A method must have been developed to

21 21 GÖLTEPE STORAGE VESSELS TIN METALLURGY AT GÖLTEPE Hematite ores that contain ppm cassiterite were not utilized. The hematite ores found at Göltepe contained 5 times more cassiterite than Kestel ores. Powdered hematite ores contained 13 times more cassiterite A method must have been developed to recognize the tin content in hematite ores. VANING KESTEL CASSITERITE VANNED (CONCENTRATED) KESTEL CASSITERITE

22 22 ASSAYING CASSITERITE GÖLTEPE SMELTING EXPERIMENT TIN PRILL FROM SEMLTING EXPERIMENT METAL FORMING METHODS

23 METAL WORKING Mechanical: To bring the metal into desired shape, generally by hammering Chemical: To change the surface appearance or to join pieces as in soldering.

23 23 METAL WORKING Mechanical: To bring the metal into desired shape, generally by hammering Chemical: To change the surface appearance or to join pieces as in soldering. Embossing: To increase the surface by hammering the metal into thin sheet and covering the modeled object made of clay or carved wood. SHAPING OF METAL Copper and its alloys can be shaped by repeated hammering and annealing. It can be hammered both hot or cold. Iron and its alloys can be forged only when hot. Cooling rate is very critical for the strength of the alloy. MECHANICAL SHAPING OF SHEET COPPER SHAPING BY HAMMERING

24 24 SHAPING SILVER PREPARATION OF COPPER BEFORE CASTING Blister copper is remelted in a crucible to keep surface area minimum and avoid contact with air. Residual inclusions float to the surface and are removed off as a dross. The molten metal is polled by unseasoned wood to reduce copper oxide that may have formed during melting back to metal EGYPTIAN CASTING OF TEMPLE DOORS Temple door OPEN MOLDS FROM TARSUS Cu Ingot Sn Ingots

25 25 OBJECTS THAT CAN BE MADE BY OPEN MOLD CASTING CASTING AN AXE WITH A SHAFT HOLE CASTING SHAFT HOLE AXE

26 26 HOLLOW CASTING BY PIECE MOLDS PIECE MOLD CASTING CHINEESE BRONZES

27 27 LOST WAX CASTING LOST WAX CASTING GRANULATION BRAZING

of copper object Heat the object to evaporate the mercury

28 28 METAL EMBOSSING MERCURY GUILDING Mix Gold or silver with mercury to form an amalgam Apply the amalgam on the surface of copper object Heat the object to evaporate the mercury Thin layer of gold or silver coat will remain on copper object.

NEOLITHIC METALLURGY IN ANATOLIA

NEOLITHIC METALLURGY IN ANATOLIA STAGES OF EARLY COPPER METALLURGY IN ANATOLA Non-metallic period (prior to 8200 BC) Single metal period (after 8200 BC). Mainly native copper is shaped for simple tools