Sedimentary Or Metamorphic (Low Grade)

Fine-grained metamorphic rock, likely slate or phyllite

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

Greenschist

Chlorite schist

Likely slate fragment

Slate; predominantly fine-grained mica/clay minerals and quartz

Phyllite

Phyllite

Slate

Slate (Low-grade foliated metamorphic rock)

Slate with Quartz Vein

Metamorphic pelitic rock with hydrothermal quartz vein

Epidote

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

Likely green-schist specimen

Greenschist, a chlorite–epidote–actinolite-bearing metamorphic rock

Greenstone / Greenschist

Greenschist (composed of chlorite, epidote, and actinolite)

Slate

Slate (Foliated Metamorphic Rock)

Small dark rock fragment, possibly shale or slate

Undetermined fine-grained silicate rock; visual identification is inconclusive

Sandstone and Quartzite Specimens

SiO2 with varying mineral/clastic inclusions

Slate

Slate

Serpentine

Serpentine group (Mg,Fe)3Si2O5(OH)4

Soapstone Carving (Pipestone/Catlinite possible)

Steatite or Argillite

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Seraphinite (Clinochlore)

Clinochlore (Mg,Fe2+)5Al(Si3Al)O10(OH)8

Likely chlorite schist

Chlorite-rich schist; commonly composed of chlorite, quartz, and mica

Slate

Slate (Foliated Metamorphic Rock)

Slate

Metamorphic Rock (Fine-grained)

Jasper (Red/Brown)

Microcrystalline Quartz (SiO2) with Iron Oxide inclusions

Red Jasper Pebble

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Slate

Slate; fine-grained metamorphosed shale, commonly quartz–muscovite/chlorite rich

Garnet Schist

Garnet-bearing Mica Schist (variety of compositions, often Al2SiO5 with X3Y2(SiO4)3)

Milky Quartz

Silicon Dioxide (SiO2)

Banded Jasper / Yellow Jasper with Chlorite or Epidote inclusions

Silicon Dioxide (SiO2) with iron oxide and silicate impurities

Slate

Phyllo-silicate based metamorphic rock

Green Calcite

Calcium Carbonate (CaCO3)

Citrine

Silicon Dioxide (Quartz variety)

Likely slate fragments

Slate, a fine-grained metamorphic rock composed chiefly of quartz, mica, and chlorite

Pietersite

Brecciated Crocidolite in Quartz (Chalcedony)

Greenstone (Greenschist)

Greenschist facies rock (containing chlorite, actinolite, and epidote)

Schist

Metamorphic Schist

Greenstone

Greenschist / Meta-basalt

Chert / Quartzite

Silicon Dioxide (SiO2)

Greenschist

Greenschist (Chlorite-Albite-Epidote Schist)

Greenschist / Serpentinite

Metamorphic rock rich in chlorite/actinolite/serpentine

Greenstone

Metabasalt

Greenstone

Greenschist (composed of actinolite, chlorite, and epidote)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Greenschist (or Serpentinite with Manganese Dendrites)

Greenschist facies metamorphic rock

Quartz and Limestone Grouping

Silicon Dioxide (SiO2) / Calcium Carbonate (CaCO3)