Sedimentary Or Metamorphic (Low Grade)

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Slate

Foliated Metamorphic Rock (primarily composed of quartz, illite, and chlorite)

Greenstone

Chlorite schist / Meta-basalt

Jadeite Jade

NaAl(Si2O6)

Slate

Foliated Metamorphic Slate

Slate

Slate (Metamorphic Rock)

Greenstone / Greenschist

Greenschist (containing Chlorite, Epidote, Actinolite)

Milky quartz-rich rock

Quartz, SiO₂; possibly quartzite or massive vein quartz

Banded gneiss (polished/tumbled cobble)

Gneiss, composed chiefly of quartz, feldspar, and mica/amphibole

Biotite-rich gneiss

Foliated quartz–feldspar–mica gneiss; mainly quartz, plagioclase/alkali feldspar, and biotite

Red Jasper

Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)

Banded Jasper (Carved)

Microcrystalline Quartz (SiO2)

Greenstone / Greenschist

Greenschist (composed of Chlorite, Epidote, Actinolite)

Greenstone (Altered Mafic Rock)

Greenschist / Meta-basalt

Greenstone (Epidosite or Altered Basalt)

Epidosite (Ca2(Al, Fe)3(SiO4)3(OH))

Greenstone (Greenstone River Pebble)

Greenschist (metamorphosed mafic igneous rock)

Greenstone

Metabasalt (Greenstone Facies)

Black Onyx

Silicon Dioxide (SiO2) - Chalcedony variety

Greenstone / Greenschist

Chlorite schist / Epidiorite / Metabasalt

Greenschist / Serpentinite Cobble

Greenschist (composed primarily of chlorite, actinolite, and epidote)

Greenstone

Greenschist facies metabasite

Greenschist

Chlorite-actinolite schist

Greenstone

Metabasalt / Greenschist

Greenstone

Greenschist

Greenstone

Protolith: Basaltic rock

Slate

Slate (foliated metamorphic rock rich in quartz, sericite, and chlorite)

Slate

Foliated Metamorphic Rock (composed of quartz, illite, and chlorite)

Greenstone

Greenschist (commonly containing Chlorite, Actinolite, and Epidote)

Greenstone / Metabasalt

Metamorphosed Mafic Rock (Greenschist facies)

Slate

Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)

Greenstone

Greenschist (composed of chlorite, actinolite, and epidote)

Jasper pebble

Silicon Dioxide (SiO2) with iron oxide impurities

Gray slate

Slate; fine-grained foliated metamorphic rock composed mainly of mica and quartz

Likely foliated metamorphic rock (slate or phyllite)

Fine-grained, foliated rock; exact identification is uncertain from the photograph

Greenstone / Graywacke

Metagraywacke or Chlorite Schist

Iron-stained slate or shale

Fine-grained, iron-oxide-stained pelitic rock; likely slate/phyllite, though the image alone cannot confirm the exact rock type

Rough Sapphire (possibly Yellow/Green Corundum)

Corundum (Al2O3)

Foliated metamorphic rock, likely slate or phyllite

Slate–phyllite; composition commonly quartz, mica, and chlorite

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Weathered metamorphic rock, likely schist or slate

Foliated pelitic metamorphic rock; commonly muscovite–chlorite schist or phyllite