Metamorphic (Low Grade)

Anthracite Coal

Anthracite (Carbon)

Greenstone (Epidosite or Serpentinite)

Metabasalt / Epidote-Chlorite Schist

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Jadeite

NaAlSi2O6; Jadeite silicate mineral

Citrine (Yellow Quartz)

Silicon Dioxide (SiO2)

Likely milky quartz

Quartz (silicon dioxide, SiO₂), possibly quartz-rich rock or calcite

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

Milky Quartz with Chlorite/Moss Infusions

Silicon Dioxide (SiO2)

Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Tumbled tiger’s-eye

Quartz variety, SiO₂, with crocidolite-derived fibrous inclusions

Kyanite (in Schist Matrix)

Kyanite (Al2SiO5)

Greenstone (or Greywacke/Metasediment Pebble)

Metamorphosed Mafic Rock / Chlorite Schist

Foliated metamorphic rock (likely phyllite or fine-grained schist)

Phyllite–schist, chiefly quartz, mica, and clay-derived silicates

Jadeite

Jadeite (NaAlSi2O6)

Small rounded, foliated metamorphic pebble (likely greenschist)

Greenschist, commonly composed of chlorite, actinolite, and albite; exact identification requires testing

Greenstone (likely altered basalt)

Metabasalt/greenschist; chiefly chlorite, actinolite, epidote, albite, and quartz

Gray metamorphic rock, likely slate or phyllite

Probably quartz–mica phyllite or fine-grained slate; exact identification requires testing

Chlorite-rich schist (probable greenschist)

Chlorite–quartz–mica schist; commonly derived from basalt or shale under greenschist-facies metamorphism

Gray slate (probable)

Slate; chiefly fine-grained mica/clay minerals, quartz, and chlorite

Polished greenstone (likely serpentine or altered basalt)

Serpentinite, mainly serpentine-group minerals (Mg₃Si₂O₅(OH)₄); exact identification requires testing

Green Schist

Greenschist (composed of Chlorite, Actinolite, and Epidote)

Quartzite pebble

Crystalline silica (SiO2)

Milky quartz-bearing rock, possibly quartzite

Quartz (SiO₂), likely in a quartzite or quartz-rich metamorphic matrix

Schist (Garnet-Mica Schist)

Garnet-Mica Schist

Quartz-rich translucent fragment

Quartz, silicon dioxide (SiO₂), possibly chalcedony or vein quartz

Eclogite

Eclogite (Omphacite + Almandine-Pyrope Garnet)

Likely quartz-rich stone, possibly quartzite or milky quartz

Quartz (silicon dioxide, SiO₂); exact rock identification is uncertain from the image

Jade

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)

Dark shale or slate fragment

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

Tumbled green aventurine/quartzite chips (probable)

Quartz, SiO₂, commonly with fuchsite or chlorite inclusions

Polished red tiger’s-eye (likely)

Quartz pseudomorph after crocidolite; chiefly SiO₂ with iron oxides

Tiger’s eye

Quartz (SiO₂) with fibrous crocidolite pseudomorphs and iron oxides

Leopard jasper (orbicular jasper)

Silicified volcanic rock, chiefly microcrystalline quartz/chalcedony (SiO₂) with feldspar and iron-oxide inclusions

Lapis Lazuli

Na6Ca2(Al6Si6O24)(S,SO4,Cl)1-2 (primarily containing Lazurite with inclusions of Calcite and Pyrite)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Dark green mineral specimen, possibly serpentine or epidote

Tentatively serpentine-group mineral, Mg₃Si₂O₅(OH)₄, or epidote, Ca₂(Al,Fe)₃Si₃O₁₂(OH)

Likely graphite-rich metamorphic rock (graphitic schist)

Graphitic schist; chiefly carbon (graphite) with quartz, mica, and possibly sulfides

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Unidentified River Rock or Mudstone

N/A (Generic rock fragment)

Aquamarine

Beryllium aluminum silicate (Be3Al2Si6O18)

Nephrite Jade

Nephrite (a variety of the Calcium magnesium iron silicate mineral series Actinolite), Ca2(Mg, Fe)5Si8O22(OH)2

White quartz fragment (likely milky quartz)

Quartz, silicon dioxide (SiO₂)