Sedimentary Or Metamorphic (Low Grade)

Gray Slate Pebble

Slate (metamorphosed mudstone/shale)

Slate

Slate (Metamorphosed Mudstone/Shale)

Greenstone

Metabasalt / Greenschist facies rock

Greenstone (Epidisite / Chlorite Schist)

Metabasalt (often contains Epidote Ca2Al2(Fe3+,Al)(SiO4)(Si2O7)O(OH) and Chlorite)

Green Schist (Greenschist)

Greenschist facies metamorphic rock

Epidote Water-Worn Pebble

Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Pyrite

Iron Sulfide (FeS2)

Greenstone (Epidosite or Serpentinite)

Metabasalt / Epidote-Chlorite Schist

Emerald

Beryl (Be3Al2(SiO3)6) colored by Chromium and/or Vanadium

Anthracite Coal

Low-grade metamorphic carbonaceous rock

Fuchsite in Quartz (or Emerald in Fuchsite / Verdite)

Chromian Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2) in Quartz Matrix

Anthracite Coal

Anthracite (Carbon C)

Anthracite Coal

Anthracite coal (Carbon)

Pyrite

Iron Sulfide (FeS2)

Anthracite Coal

Anthracite (Carbon-based sedimentary-derived metamorphic rock)

Green Calcite

Calcite (CaCO3)

Phyllite

Phyllite (Foliated metamorphic rock)

Epidote in Quartz (Epidosite)

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

Dark metamorphic cobble, likely slate or phyllite

Foliated metamorphic rock, probably carbonaceous slate/phyllite; exact identification requires testing

Fine-grained gray stone, likely slate or weathered basalt

Indeterminate; possible slate (foliated phyllite-grade shale)

Dark metamorphic rock, likely slate or phyllite

Foliated metapelite; commonly mica-rich quartz–clay mineral assemblage

Red Jasper (Beach Pebble)

SiO2 (Microcrystalline Quartz with Hematite inclusions)

Brown Jasper / River Pebble

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Slate

Slate (Metamorphic Rock)

Anthracite Coal

Anthracite

Slate or fine-grained shale

Slate; predominantly quartz, mica, and clay-derived minerals

Greenstone

Greenschist (Metamorphosed Mafic Rock)

Greenstone / Greenschist

Greenschist (composed of Chlorite, Epidote, and Actinolite)

Greenstone

Metabasalt (Greenstone facies)

Greenstone

Metabasalt / Greenstone

Eclogite

Eclogite (Omphacite-Garnet Rock)

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Dark gray metamorphic rock fragment

Likely slate or fine-grained schist; mineral composition cannot be confirmed from the image

Likely biotite-rich schist with a quartz/feldspar inclusion

Mica schist; chiefly quartz (SiO₂), feldspar, and biotite mica

Greenschist

Greenschist (containing Chlorite, Epidote, and Actinolite)

Dark shale or slate fragment

Carbonaceous shale, possibly low-grade slate; composition mainly clay minerals, quartz, and organic carbon

Greenstone

Greenschist / Meta-basalt

Greenschist

Greenschist (containing Chlorite, Actinolite, and Epidote)

Greenstone

Metabasalt / Chlorite-Epidote Schist

Epidote

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

Epidote in Matrix (Unakite-like Rock Fragment)

Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) / Altered Metamorphic Pebble

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)