mineral-based alloy (anthropogenic)
South Korean 100 Won Coin (Cupronickel)
Cupronickel Alloy (75% Cu, 25% Ni)
Hardness: Approx. 3.5-4.0 (Mohs scale); Color: Silvery-white (metallic); Luster: Metallic; Crystal structure: Face-centered cubic (FCC) lattice; Cleavage: None (ductile metal); Specific gravity: Approx. 8.9
- Hardness
- Approx
- Color
- Silvery-white (metallic)
- Luster
- Metallic
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Physical properties
Hardness: Approx. 3.5-4.0 (Mohs scale); Color: Silvery-white (metallic); Luster: Metallic; Crystal structure: Face-centered cubic (FCC) lattice; Cleavage: None (ductile metal); Specific gravity: Approx. 8.9
Formation & geological history
Formed through industrial smelting and alloying of copper and nickel ores (such as pentlandite and chalcopyrite). This specific design, featuring Admiral Yi Sun-sin, was first minted in 1970 and continues into the modern era.
Uses & applications
Legal tender/currency in South Korea; industrial cupronickel is used in marine engineering for its corrosion resistance in seawater.
Geological facts
The coin depicts Admiral Yi Sun-sin, a legendary Korean naval commander. While copper and nickel are abundant minerals, the specific combination used in coinage is engineered to prevent wear and oxidation during circulation.
Field identification & locations
Identify by the '100' and 'WON' denominations in Korean characters, and the bust of Admiral Yi. For collectors, look for high-grade luster or specific mint years (like 1970 or 1981) which are more scarce.
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