igneous
Weathered copper-bearing volcanic rock (likely altered basalt/andesite)
Hydrothermally altered basalt or andesite; green coloration may reflect chlorite, epidote, or copper minerals such as chrysocolla
AI-generated identification · may be incorrectHardness commonly 5–7; mottled green, reddish-brown, gray, and cream surface with dull to earthy luster and no obvious cleavage. The rough, irregular texture and alteration patterns are consistent with a fine-grained volcanic rock; exact identification requires a fresh break and testing.
Identified More igneous →
Explore Weathered copper-bearing volcanic rock (likely altered basalt/andesite) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness commonly 5–7; mottled green, reddish-brown, gray, and cream surface with dull to earthy luster and no obvious cleavage. The rough, irregular texture and alteration patterns are consistent with a fine-grained volcanic rock; exact identification requires a fresh break and testing.
Formation & geological history
Probably formed from volcanic lava, then chemically altered by circulating hydrothermal fluids; the red-green colors may represent oxidation and secondary mineral growth. Its geological age cannot be determined from the photograph.
Uses & applications
Usually a field or mineral-collecting specimen; copper-rich material may have limited ore value, while attractive polished pieces can be used decoratively. It is not normally used as construction stone without confirming durability and composition.
Geological facts
Green alteration minerals commonly include chlorite and epidote, while red tones can result from iron oxides. Blue-green copper minerals would be more diagnostic if visible on a fresh surface.
Field identification & locations
Look for a dense fine-grained interior, possible copper-green or blue staining, and a green streak or mineral coatings; a copper test, streak test, hardness test, and hand lens are useful. Similar rocks occur in hydrothermal and volcanic terrains worldwide.
