Red Jasper
Silicon Dioxide (SiO₂)
Category
Browse metamorphic (low grade) specimens identified by the Rock Identifier community.
Red Jasper
Silicon Dioxide (SiO₂)
Greenstone
Metabasalt
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Quartzite with Chlorite
Metamorphic Quartzite (SiO2) with phyllosilicates
Blue-gray metamorphic rock fragment
Likely slate or phyllite; exact identification is uncertain from the photograph
Anthracite Coal
Anthracite (Hard Coal)
Likely black shale or slate fragment
Slate; predominantly fine-grained mica/clay minerals and quartz
Tumbled black-and-gold tiger’s-eye
Quartz pseudomorph after crocidolite; SiO₂ with iron oxides
Greenstone or Chlorite Schist
Greenschist / Chlorite schist
Emerald In Matrix
Beryl (Be3Al2Si6O18) with trace Chromium/Vanadium
Mica Schist
Foliated Metamorphic Rock (Schist)
Tiger's Eye
Quartz with riebeckite inclusions (SiO2)
Graphitic schist (probable)
Graphite-bearing mica schist; chiefly quartz, mica, and graphite
Green schist (likely chlorite schist)
Chlorite schist; commonly dominated by chlorite, actinolite, epidote, quartz, and feldspar
Greenstone (probable altered basalt)
Chlorite–epidote–actinolite-rich greenschist; composition commonly derived from basalt
Soapstone (talc-rich schist)
Talc schist; chiefly hydrated magnesium silicate, Mg₃Si₄O₁₀(OH)₂
Calcite-rich limestone or marble fragment
Calcite (CaCO₃), likely recrystallized carbonate rock
Likely greenstone (metamorphosed basalt)
Greenschist or chlorite–epidote altered basalt; commonly composed of chlorite, epidote, actinolite, albite, and quartz
Green Greenstone / Celadonite-bearing Metamorphic Rock
Greenschist / Celadonite / Serpentinitic pebble
Greenstone / altered mafic rock
Likely chlorite–actinolite metabasalt (greenschist); exact identification requires testing
Greenstone (Greenschist facies)
Greenschist (composed primarily of Chlorite, Actinolite, and Epidote)
Greenstone
Greenschist (Greened Metabasalt)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2), a variety of Actinolite-Tremolite
Greenstone
Metabasalt / Greenschist facies rock
Greenstone
Greenschist / Meta-basalt
Tumbled green serpentine (likely nephrite jade imitation/alternative)
Serpentine-group minerals, chiefly antigorite and lizardite; composition approximately Mg₃Si₂O₅(OH)₄
Pyrite (Limonite Pseudo-morph after Pyrite)
Iron sulfide (FeS2) transitioning to Iron oxide-hydroxide (FeO(OH)·nH2O)
Anthracite Coal with Sulfur staining
Anthracite (Carbon C with impurities)
Greenstone
Metamorphic mafic rock (greenschist facies)
Jadeite (Nephrite-Jadeite blend)
Jadeite (NaAlSi2O6)
Tumbled tiger’s-eye
Tiger’s-eye (chatoyant quartz), SiO₂, pseudomorphic fibrous quartz after crocidolite
Rounded greenstone cobble
Likely greenschist or altered basalt; composition commonly chlorite, epidote, actinolite, albite, and quartz
Serpentinite
Serpentinite (Hydrated Magnesium Silicate Mg3Si2O5(OH)4)
Greenstone (Epidote/Chlorite-rich Metabasalt)
Greenschist / Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))
Greenschist / Migmatite
Regional Metamorphic Complex (Facies: Greenschist to Amphibolite)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Epidote in Quartz
Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) in Milky Quartz (SiO2)
Dark gray metamorphic rock, likely slate or phyllite
Slate/phyllite; commonly quartz–mica–chlorite aggregate
Ruby (Corundum)
Aluminum oxide (Al2O3) with Chromium traces
Ruby
Corundum (Al2O3 with Chromium traces)
Green Schist
Greenschist (composed of chlorite, epidote, and actinolite)