Rock Identifier
Iron Slag (Industrial Byproduct) (Anthropogenic pyrometallurgical residue) — mineral
mineral

Iron Slag (Industrial Byproduct)

Anthropogenic pyrometallurgical residue

Hardness: 5.5-7.0 (Mohs); Color: Dark grey, brownish-red to black; Luster: Metallic to dull; Structure: Amorphous/vesicular; Cleavage: None; Specific Gravity: 2.8-4.0

Hardness
5
Color
Dark grey, brownish-red to black
Luster
Metallic to dull
Identified More mineral
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Physical properties

Hardness: 5.5-7.0 (Mohs); Color: Dark grey, brownish-red to black; Luster: Metallic to dull; Structure: Amorphous/vesicular; Cleavage: None; Specific Gravity: 2.8-4.0

Formation & geological history

Formed as a byproduct of smelting ores (specifically iron or copper) where molten waste cools rapidly. The coordinates point to Kerman, Iran, a region famous for thousands of years of metallurgical history and copper/iron mining.

Uses & applications

Historically a waste product, but modernly used in road construction, concrete aggregate, and sometimes for historical/archaeological study of ancient smelting techniques.

Geological facts

Many amateurs mistake slag for meteorites because of its metallic sheen, weight, and fusion-crust-like texture. However, the presence of small spherical bubbles (vesicles) and its occurrence near historical mining sites usually confirms it as slag.

Field identification & locations

Identify by looking for air bubbles (vesicles), which real meteorites do not have. Use a magnet; many iron-rich slags are magnetic. In the Kerman region, this is likely related to historical smelting operations.