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| Gold is a naturally occurring element; it is a soft yellowish metal with a high specific gravity. |
| It has the highest Malleability of any metal, is the most ductile of all metals, and is also very sectile. |
| It is a precious or noble metal and thus inert, traditionally highly prized due to its relative rarity and great beauty. |
| Its physical characteristics and attributes make it unique, and have lead inevitably to its development as a measure
and form of value, money and wealth. |
| Its use in industry is increasing, but the traditional roles of money, bullion and Jewellery are still its most common usage. |
| Malleable: |
Can easily be beaten or hammered flat. (9sq Metres) |
| Ductile: |
Can readily be drawn into a wire. (75km long) |
| Sectile: |
Can be cut by a knife |
| Specific Gravity: |
19.3 in its pure state, but when found naturally, can be from 12 - 19, depending upon the alloy. (19.2-19.4) |
| Hardness: |
2.5 - 3.0 |
| Fracture: |
Hackly |
| Streak: |
Yellow |
| Melting Point: |
1,060 ºC – 1,913 ºF |
| Lustre: |
Metallic, opaque except in thin foil, where it allows the transmission of Green & Blue light. |
| Crystal: |
Rare, but usually octahedral, dodecahedral or cubic. |
| Colour: |
Distinctive golden yellow, but may vary from white or silver to reddish with natural alloys of Silver & Copper, can be coated black by Ironstone or Manganese. |
| Vapour: |
If boiled, its vapour is green. |
| Chemical Symbol: |
Au (from the Latin aurum) |
| Atomic Number: |
79 |
| Atomic Weight: |
197.2 |
| Soluble only in Aqua Regia, (1 part Nitric Acid to 3 parts Hydrochloric Acid). |
| No single acid or caustic alkaline will attack Gold. |
| Other attributes: |
High conductor of electricity, resistant to moderate heat, ability to alloy, effective shield against cosmic radiation, in plating operations, it takes only a couple of millionth’s of an inch to effectively protect a component from corrosion, lack of chemical taste in dentistry. |
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If refined, its powder is a chocolate brown colour. |
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Gold may occur as nuggets, grains, flakes, specs, flour, wire gold, leaf gold, crystal, sheet gold, moss gold, mustard, tree gold, foil, hair, sponge, thread, rust, powder, float, reef, leader, mullocky leader, and in other forms and ways. |
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by Garry Gatfield |
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