igneous
Dark, coarse-grained rock; likely gabbro or diorite
Undetermined mafic-to-intermediate intrusive igneous rock; exact identification requires closer examination
AI-generated identification · may be incorrectDark gray with lighter mineral flecks and a coarse, crystalline texture. Likely dominated by plagioclase and dark pyroxene or amphibole; hardness and specific gravity cannot be determined reliably from the image.
Identified More igneous →
Explore Dark, coarse-grained rock; likely gabbro or diorite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Dark gray with lighter mineral flecks and a coarse, crystalline texture. Likely dominated by plagioclase and dark pyroxene or amphibole; hardness and specific gravity cannot be determined reliably from the image.
Formation & geological history
Likely formed by slow cooling of magma underground, allowing visible crystals to grow; its geological age and location of origin are unknown.
Uses & applications
Commonly used as crushed aggregate and dimension stone; this unpolished specimen has little commercial value but may interest collectors.
Geological facts
Gabbro and diorite can look similar in photographs; mineral proportions and crystal details are needed to distinguish them.
Field identification & locations
Look for interlocking visible crystals and a dark overall color; a fresh surface and hand lens can help identify the minerals. The image alone does not establish a locality.
