ANCIENT GOLD MALLEABILITY OF GOLD EARLIEST GOLD OBJECTS

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Geoffrey Lewis
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A strip of gold with 2 mm thickness can be beaten to an equivalent elongation of about 186,000 times or to 99.9996% re duction in thickness.

1 MALLEABILITY OF GOLD ANCIENT GOLD It can be beaten into a very thin leaf without a need of anneal. It can be reduced to a foil that is nm (10-9 m), about atoms in thickness. A strip of gold with 2 mm thickness can be beaten to an equivalent elongation of about 186,000 times or to % re duction in thickness. EARLIEST GOLD OBJECTS VARNA GRAVES Varna burrials,, 3000 gold pieces weighing about 6.5 Kg. And dated 4000 BC. Ur, Late Ubaid period, gold 4000 BC Tepe Gawra,, Northern Iraq, various gold jewelry, Late Chalcolithic. Susa,, Southern Mesopotamia, Dog shaped pendant, 3250 BC. 1

2 ANCIENT GOLD IN TURKEY No gold before 3000 BC Earliest evidence at Troy I. From Troy IIg. Gold objects of Alacahöyük and Horoztepe at the 2nd half of third millennium BC. Gold objects from Mahmatlar,, third millennium BC. Gold objects from Kültepe,, beginning of 2nd millennium BC GOLD FROM TROYA 2

3 ALACAHÖYÜK GOLD HOROZTEPE GOLD PITCHER 3

GOLD ONJECTS FROM MAHMATLAR GOLD OBJECTS FROM KÜLTEPE TYPES OF GOLD

Green gold Blue gold White gold Pale yellow % Au 79 50 86 30 75

3 % Cu 50 Others (%) 21% Al 7-17 % Fe 25% Fe 8-10% Ni, 2-9%Zn 1.

4 GOLD ONJECTS FROM MAHMATLAR GOLD OBJECTS FROM KÜLTEPE TYPES OF GOLD SPECIFIC GRAVITY OF GOLD ALLOYS Purple gold Dark red gold Grey gold Green gold Blue gold White gold Pale yellow % Au % Ag % Cu 50 Others (%) 21% Al 7-17 % Fe 25% Fe 8-10% Ni, 2-9%Zn 1.7-8% Ni Specific gravity (g/cm 3 ) % Gold content 98±0.5 93±1.0 86±2.3 19±3.5 71±5.0 62±6.5 4

DENSITY OF MATERIALS REFINING OF GOLD Cupellation: Oxidized elements like Cu, Zn, Bi, Sb, Pb etc. are eliminated in a cupel. Amalgamation: Mercury readily forms an alloy (amalgam) with gold.

5 DENSITY OF MATERIALS REFINING OF GOLD Cupellation: Oxidized elements like Cu, Zn, Bi, Sb, Pb etc. are eliminated in a cupel. Amalgamation: Mercury readily forms an alloy (amalgam) with gold. Mercury will thus remove gold from powdered low grade gold ores. Cyanidation: 4Au + 8CN - + 2H 2 O + O 2 4[Au(CN) 2 ] - + 4OH - 4[Au(CN) 2 ] - + Zn 2Au + [Zn(CN) 4 ] -2 PURIFICATION OF GOLD GOLD REFINING FROM AGRICOLA 5

6 ELECTRUM Natural alloy of Gold and Silver is known as Electrum. All Naturally occurring cold contains between 2-30 % silver and must be refined. ANCIENT LYDIA REGIONAL MAP OF SARDIS SARDIS COINS Poctulus River 6

7 KING CROSES ON PILE SARDIS BIN TEPELER PARTING OF SILVER AND GOLD PARTING VESSEL 7

8 SARDIS PARTING FURNACE SARDIS CUPPELS GOLD WORKSHOP AT SARDIS 8

9 GOLD PRILLS ON CRUCIBLE GOLD FOILS FROM SARDIS SEM OF GOLD FOIL SEM OF GOLD FOIL 9

APPLICATION OF GOLD ON OBJECTS Embossing

10 APPLICATION OF GOLD ON OBJECTS Embossing or gilding an object with gold foil or gold leaf. Amalgam gilding of a copper object followed by heating to expel mercury. Silvering: Silver amalgam can be applied onto copper or bronze objects. Electroplating EGYPTIAN GOLD BEATING Egyptian gold embossed objects TUUANKHANUM S S TOMB 10

GRANULATION Small grains of gold is used in the decorative

Tiny spheres of gold forms instantly when a small amount of the

Grains can also be made by cutting short lengths of wire and

GOLD GRANULATION GOLD GRANULATION GOLD SOLDERING An alloy of Au

This alloy has a eutectic melting point of 878 o C, which is 185 o

11 GRANULATION Small grains of gold is used in the decorative fabrication of jewelry. Tiny spheres of gold forms instantly when a small amount of the molten metal is poured lowly into water. Grains can also be made by cutting short lengths of wire and heating until a droplet is formed. GOLD GRANULATION GOLD GRANULATION GOLD SOLDERING An alloy of Au and Cu at proportions of 82:12 is used for gold soldering. This alloy has a eutectic melting point of 878 o C, which is 185 o C below that of pure gold. Solder is made paper thin and applied in the form of narrow strip which the grains were placed and gently heated on both sides at once until the solder flows. 11

12 Cu-Au-Ag THERNARY PHASE DIAGRAM BRASING MERCURY AMALGAMATION SURFACE ENRICHMENT 12

13 GOLD WOKSHOP AT KAPALIÇARŞI MELTING GOLD IN A CRUCIBLE POURING INTO METAL MOLD 13

14 GOLD BAR INGOTS DRAWING WIRE DRAWING WIRE 14

15 Gold chain making World gold production UTILIZATION OF GOLD İSTANBUL GOLD REFINARY Jewelry Gold coins Electronics Dental work Other Industries 15

16 FACTS ABOUT GOLD World gold reserves are 42,500 tons Turkish gold reserves are 6,500 tons In 2002, World gold production was 2,500 tons. Annual Turkish gold import is 200 tons. 1 ounce of gold is 31.1 grams = $ Gold possesses by an Italian = 0.70 gr an Indian = 0.02 gr a Turk = 2.50 gr MYTHS ABOUT GOLD Paris gives the golden apple to Aphrodite as the most beautiful woman, which eventually starts the Trojan war. Trips of Argonauts to find the golden fleece. Story of King Midas who wished Dionissos that what ever he touched be turned into gold. Long search of alchemists to produce gold from other elements. Main reason for the trip of Columbus is the gold he promised to Isabella. 16

V349 (CLF5043) Halide Free No Clean Core Wire Fine Wire Applications

Pb V349 (CLF5043) Halide Free No Clean Core Wire Fine Wire Applications INTRODUCTION Viromet* 349, with a composition of Sn/Ag/Cu/In + X, is one of the high-performance lead free solder available in the