General Gold Information:
| Chemical Formula: | Au |
| Composition: | Molecular Weight = 196.97 gm |
| Gold 100.00 % Au | |
| Empirical Formula: | Au |
| Environment: | Quartz veins and alluvial deposits. |
| IMA Status: | Valid Species (Pre-IMA) Prehistoric |
| Name Origin: | Anglo Saxon, of uncertain origin. |
| Synonym: | Electrum – Ag Alloy |
Gold Image:
Images: 
Gold Silver
Comments: Very well crystallized Electrum (Silver rich gold) on quartz.
Images: 
Gold
Comments: Well crystallized bright metallic
Images: Gold Isomertieite Arsenopalladinite Bornite
Comments: Light grayish grain of intimately intergrown Isomertieite and arsenopalladinite (in the Section (from microprobe analysis) in Reflected light.
Images: Gold Petzite
Comments: Dark, stubby petzite crystals with native gold On Quartz.
Images: Gold
Comments: Two skeletal octahedral crystals of gold
Physical properties of gold:
| Cleavage: | None | ||
| Color: | Yellow, Pale yellow, Orange, Yellow white, Reddish white. | ||
| Density: | 16 – 19.3, Average = 17.64 | ||
| Diaphaniety: | Opaque | ||
| Fracture: | Hackly – Jagged, torn surfaces, (e.g. fractured metals). | ||
| Habit: | Arborescent – “Tree like” growths of branched systems (e.g. silver). | ||
| Habit: | Granular – Generally occurs as anhedral to subhedral crystals in matrix. | ||
| Habit: | Platy – Sheet forms (e.g. micas). | ||
| Hardness: | 2.5-3 – Finger Nail-Calcite | ||
| Luminescence: | None. | ||
| Luster: | Metallic | ||
| Magnetism: | Nonmagnetic | ||
| Streak: | yellow | ||
| Atomic number | 79 |
| Atomic mass | 196.9655 g.mol -1 |
| Electronegativity according to Pauling | 2.4 |
| Density | 19.3 g.cm-3 at 20°C |
| Melting point | 1062 °C |
| Boiling point | 2000 °C |
| Vanderwaals radius | 0.144 nm |
| Ionic radius | 0.137 nm (+1) |
| Isotopes | 7 |
| Electronic shell | [ Xe ] 4f14 5d10 6s1 |
| Energy of first ionization | 888 kJ.mol -1 |
| Energy of second ionization | 1974.6 kJ.mol -1 |
| Standard potential | +1,68 V ( Au+/ Au ) |
| Discovered | c.a. 3000 BC |
Optical Properties of Gold:
| RL Color: | Gold-yellow when pure, silver white to copper-red when impure, blue and green in transmitted light. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Reflectivity |
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Calculated Properties of Gold:
| Electron Density: | ?electron=15.5 gm/cc note: ?Gold =19.3 gm/cc. |
| Fermion Index | Fermion Index = 0 Boson Index = 1 |
| Photoelectric: | PEGold =1,695.89 barns/electron U=PEGold x ?electron=26228.24 barns/cc. |
| Radioactivity: | GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Gold is Not Radioactive |
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