igneous
Vesicular basalt (likely weathered lava rock)
Basalt, predominantly calcium-rich plagioclase, pyroxene, and commonly olivine; vesicular texture from gas bubbles
AI-generated identification · may be incorrectDark gray to greenish-black, dull to weakly vitreous luster, fine-grained matrix with rounded cavities; hardness about 5–6 Mohs, no visible cleavage, typically dense except for vesicles. The opening appears natural rather than a crystal-lined geode.
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Physical properties
Dark gray to greenish-black, dull to weakly vitreous luster, fine-grained matrix with rounded cavities; hardness about 5–6 Mohs, no visible cleavage, typically dense except for vesicles. The opening appears natural rather than a crystal-lined geode.
Formation & geological history
An extrusive igneous rock formed when basaltic lava cooled rapidly at or near Earth’s surface, trapping volcanic gases; specimens may range from recent lava to ancient flows of almost any geological age.
Uses & applications
Used as aggregate, road base, riprap, landscaping stone, and sometimes carving material; attractive vesicular pieces are collected but generally have low commercial value.
Geological facts
Vesicles are gas bubbles preserved in lava; green coloration may indicate weathering or olivine/chlorite minerals. It is not confidently identifiable as a meteorite from this image.
Field identification & locations
Look for a fine-grained dark matrix, irregular gas cavities, heavy weight, and absence of metallic flecks or glassy fracture; common worldwide in volcanic regions, including Hawaii, Iceland, and oceanic islands.
