mineral-like byproduct
Slag
Anthropogenic Vitreous Silica/Iron oxides
Hardness: 5-7 (Mohs scale); Color: Black, dark gray, or glassy brown; Luster: Vitreous to metallic; Structure: Amorphous (non-crystalline) or porous; Cleavage: None; Specific Gravity: Varies (2.5-4.0).
- Hardness
- 5-7 (Mohs scale)
- Color
- Black, dark gray, or glassy brown
- Luster
- Vitreous to metallic
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Physical properties
Hardness: 5-7 (Mohs scale); Color: Black, dark gray, or glassy brown; Luster: Vitreous to metallic; Structure: Amorphous (non-crystalline) or porous; Cleavage: None; Specific Gravity: Varies (2.5-4.0).
Formation & geological history
Formed as a byproduct of smelting ores (iron, steel, or copper) to separate metal from raw rock. It is a man-made material often found in industrial areas or historical smelting sites.
Uses & applications
Commonly used as road ballast, railway bedding, raw material for cement, and occasionally as an abrasive or in rock wool insulation.
Geological facts
Slag is often mistaken for meteorites due to its dark color, heavy weight, and metallic luster. However, the presence of bubbles (vesicles) is a definitive sign that it is slag rather than a meteorite.
Field identification & locations
Look for a glassy texture or a series of small circular holes (gas bubbles) caused by escaping gases during the cooling process. It is frequently found near old railways, mines, and industrial docklands.
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mineral