Gold
Gold is a chemical element with the symbol Au (from Latin: aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally. Here are some key points about gold:
Physical Properties
- Appearance: Gold is a soft, bright, dense, malleable, and ductile metal with a yellow color when in bulk form, although it can be black or purple when finely divided.
- Density: Its density is 19.3 grams per cubic centimeter, which is significantly higher than most common metals.
- Malleability and Ductility: It can be hammered into thin sheets (gold leaf) and drawn into very thin wires.
- Conductivity: Gold is an excellent conductor of electricity and heat.
Chemical Properties
- Chemical Inactivity: Gold is chemically inert, meaning it does not react with oxygen or water at any temperature, making it resistant to corrosion and oxidation.
- Noble Metal: Due to its chemical inertness, gold is classified as a noble metal along with metals like platinum and silver.
History
- Early Use: Gold has been used by civilizations since ancient times. It was first mentioned in the Mesopotamian Civilization around 2600 BC.
- Cultural Significance: Throughout history, gold has been associated with wealth, power, and divinity. It was used for jewelry, coinage, and as a form of currency.
- Gold Standard: In the 19th and early 20th centuries, many countries adopted the Gold Standard, where the value of a country's currency was directly linked to gold.
Extraction and Production
- Mining: Gold is typically found in ores and can be extracted through various mining techniques including placer mining, hard rock mining, and by-product mining.
- Refining: After extraction, gold is refined using processes like cyanidation, amalgamation, or smelting to separate it from impurities.
Uses
- Jewelry: Over 50% of the world's gold supply is used in jewelry.
- Investment: Gold bars, coins, and other forms of gold bullion are popular investment vehicles.
- Electronics: Gold's conductivity makes it ideal for use in connectors, switch and relay contacts, and other electronic components.
- Medicine: Gold compounds have been used in medicine for treating conditions like rheumatoid arthritis.
- Industry: Gold is used in the manufacturing of scientific instruments, glass making, and in aerospace applications due to its unique properties.
Global Supply
- Production: The world's largest gold-producing countries include China, Australia, Russia, and the United States.
- Recycling: A significant portion of the gold supply also comes from recycling, particularly from electronic waste.
Current Market and Value
- Price: The price of gold is influenced by many factors including inflation, currency values, and global economic stability.
- Trading: Gold is traded on commodity markets, and its value can be tracked through various indices and futures markets.
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