Gold is one of the precious metals that has been known by man the highly value of it. In Latin, gold is called Aurum and that’s how the gold chemical symbol (Au). From the Periodic Table Of Elements, gold is identified as a intermediary metal with the following characteristics :-
- Symbol: Au
- Atomic number: 79
- Atomic mass: 196.96655 amu
- Number of protons/electrons: 79
- Number of neutrons: 118
- Melting point: 1,064.43°C (1,337.58°K, 1,947.97°F)
- Boiling point: 2,807.0°C (3,80.15°K, 5,084.6°F)
- Density @ 293°K: 19.32 grams per cubic centimeter
- Crystal structure: cubic
Today gold perhaps been alloyed with assorted other metals to give it special properties. Gold has a metallic luster and is sun yellow in its pure form. Gold purity can be expressed in parts per 1000 using fineness as its metallurgical term of indicator. Most pure gold have a fineness of 999.9 parts of 1,000. Carat is the unit that been used to measured the amount of gold in an alloy. Alloys which is called fine or pure gold is 24 carat and the lesser the carat values indicates the proportion of fine gold content as fraction of 24. For example, an 18 carat gold item contain 18/24 fine gold and 6/24 other alloy by weight.
- 24 carat = 99.9%
- 22 carat = 91.6%
- 20 carat = 83.5%
- 18 carat = 75.0%
