Historical UsesThe oldest golden treasure in the world, dating from 4,600 BC to 4,200 BC, was discovered at the site of 'The Thracian Horseman" modern Day Bulgaria and Greece region of the Balkans.. Later utilized in Egyptian and Roman Empires, Gold Leaf was elevated to its highest artistic and technical achievements in the Byzantine Empire; techniques which are still used around the world today, though mastered by few.
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One gram of gold can be hammered out into a thin sheet of gold a meter in area... the gramira this is how artists were paid for centuries, and the best artists put some of themselves back in every creation Properties of Gold
• Density: 19.30 g·cm−3 [in g·cm−3 - water is 1, Pb is 11.3, Os 22.6]
• Color: yellow (copper and cesium are the only other colored metallic elements) • Total all-time production worldwide: 161,000 tonnes by 2009 • Physical properties: most malleable and ductile of metals • Unaffected by air, water or most corrosive compounds • Dissolves with aqua regia, cyanide and mercury • Conversion: 31.01 tonnes equals 1 Moz. • Modern uses: jewelry, dental, electronics, computers, bars, coins • Monetary use: hard asset to support paper currency • Recycling: most of the gold ever mined is still in use • Earliest mining: alluvial mining in middle-east and Africa several thousand years ago • Price in $US: $250 to $1400 since 1995. Pegged to US dollar at $35 before 1980s. • Price in terms of labor: one ounce of gold has been worth approximately one to two weeks labor [has remained in this bracket for centuries] • Melting point: 1064 °C • Boiling point: 2856 °C • Atomic weight: 79 • Atomic mass: 197.0 • Periodic table column: below Cu and Ag • Periodic table row: after Os, Ir, Pt; before Hg, Tl, Pb, Bi • Similar elements: include Ag, Cu, PGEs, Bi depending upon chemical environment. • Oxidation states: -1, 1, 2, 3, 4, 5. Note +1 and +3 • Electronegativity: 2.54 Pauling scale, Electron configuration: [Xe] 4f14 5d10 6s1 • Ionisation energy: 1st 890.1 kJ.mol-1, 2nd 1980 kJ.mol-1 • Atomic radius 144 pm, Covalent radius 136 +/-6 pm • Au1+ 137 pm, very large, Au3+ 85 pm, • Co-ordination chemistry: linear (Au1+), square planar (Au3+)• Au1+ 137 pm, very large, Au3+ 85 pm, • It radiates eternal beauty |