metamorphic
Greenstone / altered mafic rock
Likely chlorite–epidote–actinolite schist or altered basalt (greenstone); exact identification requires thin-section or chemical testing.
AI-generated identification · may be incorrectFine- to medium-grained, dull to weakly waxy luster, mottled green-gray with rusty iron-oxide staining and pale patches; likely hardness 5–6, with poorly visible cleavage and dense, tough texture. The rounded shape suggests water wear or tumbling.
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Physical properties
Fine- to medium-grained, dull to weakly waxy luster, mottled green-gray with rusty iron-oxide staining and pale patches; likely hardness 5–6, with poorly visible cleavage and dense, tough texture. The rounded shape suggests water wear or tumbling.
Formation & geological history
Probably metamorphosed or hydrothermally altered basalt, where chlorite, epidote, actinolite, and albite replaced original mafic minerals; such rocks range from Precambrian to Cenozoic in age and form in oceanic crust, greenstone belts, or subduction-related terranes.
Uses & applications
Used locally as decorative stone, landscaping material, lapidary rough, and occasionally for carvings or cabochons; it has limited commercial value unless unusually attractive or confirmed as jade.
Geological facts
Its green color is commonly produced by chlorite, epidote, or actinolite rather than true jade minerals. Similar-looking material can include serpentine, greenschist, or nephrite, which cannot be reliably distinguished from this photograph alone.
Field identification & locations
Check for a very fine interlocking texture, green metamorphic minerals, high density, and lack of obvious glassy fracture; a streak, hardness, specific-gravity, and microscope test help separate it from jade and serpentine. Common in metamorphic belts and altered volcanic terrains worldwide.
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