industrial by-product
Slag
Hard, dense, often glassy or porous, dark color (brown, black), dull to somewhat shiny luster, irregular fracture.
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Physical properties
Hard, dense, often glassy or porous, dark color (brown, black), dull to somewhat shiny luster, irregular fracture.
Formation & geological history
Formed as a by-product of metal smelting or refining processes, where impurities are separated from the molten metal.
Uses & applications
Often used in construction, road base, and as aggregate in concrete.
Geological facts
Slag is frequently mistaken for meteorites due to its weird appearance and sometimes high density. It can sometimes contain vesicles (gas bubbles).
Field identification & locations
Identify by its glassy texture, vesicles, and location (often found near old industrial sites or railroad tracks). It is common and typically not valuable.
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