Metal / Man-made mineral-like object
United States Quarter Dollar
Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)
Hardness: 3.5-4.0 on Mohs scale; Color: Silver-grey exterior, copper-orange edge; Luster: Metallic; Structure: Crystalline lattice (solid solution); Specific Gravity: ~8.92.
- Hardness
- 3
- Color
- Silver-grey exterior, copper-orange edge
- Luster
- Metallic
Identified More metal / man-made mineral-like object →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 3.5-4.0 on Mohs scale; Color: Silver-grey exterior, copper-orange edge; Luster: Metallic; Structure: Crystalline lattice (solid solution); Specific Gravity: ~8.92.
Formation & geological history
Formed via industrial minting processes (rolling, blanking, annealing, and upsetting) at US Mint facilities. Current 'clad' composition was established in 1965 to replace silver coinage.
Uses & applications
Legal tender currency for economic transactions; widely used in vending machines, laundromats, and as a standard measurement of size for rock/mineral identification photography.
Geological facts
This specific coin appears to be from the 'America the Beautiful' Quarters Program (2010-2021). Quarters are frequently used by geologists as a 'scale of reference' in field photos to provide a known diameter (24.26 mm).
Field identification & locations
Identified by its diameter (0.955 in), reeded edge, and distinctive obverse portrait of George Washington. Found in pockets, cash registers, and urban environments globally.
More like this
Other metal / man-made mineral-like object specimens
Ring with an Orange Inlay
N/A (Man-made object)
Man-made Object (Ring)
Not a geological specimen
N/A (man-made object)
N/A
Titanium-coated Metal Cube (Man-made Fidget Toy)
Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)
Mineral alternative / Synthetic
Aluminum Slag
Anthropogenic Aluminum (Al)
mineral
Metal Chain Belt with Square Plates
Not applicable (man-made)
Man-made Object (Metalwork)
Man-made Synthetic Material (Plastic/Composite)
Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)
Non-geological / Synthetic