metamorphic
Unakite-like polished pebble
Epidote–K-feldspar–quartz rock (likely altered granite; identification from image is provisional)
AI-generated identification · may be incorrectHardness about 6–7 Mohs; dark green-gray, fine-grained, with salmon-pink patches, dull to weakly vitreous luster, and no obvious cleavage on the rounded surface. The pink areas are likely potassium feldspar, while green areas are epidote with possible quartz or chlorite.
Identified More metamorphic →
Explore Unakite-like polished pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness about 6–7 Mohs; dark green-gray, fine-grained, with salmon-pink patches, dull to weakly vitreous luster, and no obvious cleavage on the rounded surface. The pink areas are likely potassium feldspar, while green areas are epidote with possible quartz or chlorite.
Formation & geological history
Forms when granitic rock undergoes hydrothermal alteration, converting minerals to epidote and leaving pink feldspar; commonly Precambrian to Paleozoic in age depending on locality. This specimen appears naturally water-worn or tumbled and polished.
Uses & applications
Used as a lapidary stone for cabochons, beads, carvings, and decorative pebbles; rarely used as construction aggregate. Common specimens generally have modest collector value.
Geological facts
Classic unakite is mottled pink and green, but darker epidote-rich varieties can resemble this specimen. Image-only identification cannot exclude epidote-bearing granite, altered basalt, or another greenstone.
Field identification & locations
Commonly found in metamorphic and hydrothermally altered terrains, including the Appalachian region, South Africa, Brazil, and China. A hand lens, streak test, hardness test, and examination of a fresh break help distinguish feldspar-rich unakite from basalt or serpentine.
More like this
