igneous
Crushed Stone (Basalt/Gabbro)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Hardness: 6-7 Mohs; Color: Dark grey to black with light speckles; Luster: Dull to sub-metallic; Structure: Fine to medium-grained; Cleavage: Often poor/irregular; Specific Gravity: 2.8-3.0
- Hardness
- 6-7 Mohs
- Color
- Dark grey to black with light speckles
- Luster
- Dull to sub-metallic
Identified More igneous →
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Physical properties
Hardness: 6-7 Mohs; Color: Dark grey to black with light speckles; Luster: Dull to sub-metallic; Structure: Fine to medium-grained; Cleavage: Often poor/irregular; Specific Gravity: 2.8-3.0
Formation & geological history
Formed through the cooling and solidification of basaltic magma or lava. These rocks are primary components of the oceanic crust and volcanic regions; these specific pieces are typically processed via industrial crushers.
Uses & applications
Extensively used in construction for road base, concrete aggregate, railroad ballast, and landscaping gravel.
Geological facts
Basalt is the most common volcanic rock on Earth and also makes up most of the surface of the Moon and Mars.
Field identification & locations
Identify by its dark color, high density, and fine grain size. Often found in gravel driveways, construction sites, and near volcanic outcroppings.
