igneous
Slag
Anthropogenic silicate slag
AI-generated identification · may be incorrectHardness varies from 5 to 6 on the Mohs scale depending on composition. Typically black, dark green, or gray with a glassy to vitreous luster and vesicular or crystalline texture.
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Physical properties
Hardness varies from 5 to 6 on the Mohs scale depending on composition. Typically black, dark green, or gray with a glassy to vitreous luster and vesicular or crystalline texture.
Formation & geological history
Formed as a byproduct of smelting ore to purify metals, cooling rapidly from industrial high-temperature melts.
Uses & applications
Used in road construction, as railway ballast, and in cement production. Often collected as industrial curiosities.
Geological facts
Slag is frequently mistaken for meteorites due to its dark, glassy appearance and vesicles caused by trapped gas bubbles.
Field identification & locations
Can be identified by its glassy luster, vesicular bubbles, and occasional magnetic response from iron content. Found near historic smelting sites and industrial dumps.
