igneous
Weathered volcanic rock, possibly vesicular basalt
Likely basalt or another mafic volcanic rock; exact identification is uncertain from the image
AI-generated identification · may be incorrectGray-brown, rounded specimen with irregular pits and a rough, weathered surface. If basalt, it is typically fine-grained, mainly plagioclase and pyroxene, with Mohs hardness around 6; crystal structure and cleavage are not distinguishable here.
Identified More igneous →
Explore Weathered volcanic rock, possibly vesicular basalt in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Gray-brown, rounded specimen with irregular pits and a rough, weathered surface. If basalt, it is typically fine-grained, mainly plagioclase and pyroxene, with Mohs hardness around 6; crystal structure and cleavage are not distinguishable here.
Formation & geological history
Likely formed when lava cooled at or near the surface; pits may be vesicles left by escaping gas. The specimen’s age and exact formation environment cannot be determined from the photo.
Uses & applications
Commonly collected as a natural specimen; basalt is also widely used as crushed aggregate, paving stone, and construction material.
Geological facts
Vesicles are gas-bubble cavities preserved in volcanic rock, though surface pits can also result from weathering.
Field identification & locations
Look for a dense, fine-grained interior and genuine gas cavities; fresh fracture, hardness, and a hand lens would help distinguish basalt from other porous rocks. Basalt occurs in volcanic regions worldwide.
