Metamorphic (Low Grade)

Epidotite (Unakite-related Epidote)

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))

Anthracite Coal

Low-grade metamorphic carbonaceous rock

Epidote

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

Greenschist

Greenschist (comprising Actinolite, Chlorite, and Epidote)

Greenschist (Greenstone)

Greenschist

Greenstone (Greenschist)

Greenschist facies rock (containing chlorite, epidote, actinolite)

Porphyritic Andesite or Basalt

Porphyritic Intermediate/Mafic Igneous Rock

Greenstone (Epidosite)

Epidosite (Metamorphosed Basalt/Diabase)

Greenstone (Epidote/Chlorite Rich Rock)

Metabasalt (often contains Epidote Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH))

Greenstone

Greenschist / Meta-basalt

Pyrite in Slate

Iron Disulfide (FeS2) in Low-grade Metamorphic Rock

Epidote in Matrix

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

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Epidote in Matrix (Unakite-related)

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

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

Yellow Jade

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

Slate

Slate (Foliated Metamorphic Rock)

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

Epidote

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

Epidote

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

Garnet Schist

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

Sandstone and Quartzite Specimens

SiO2 with varying mineral/clastic inclusions

Yellow Jade (Nephrite or Quartzite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jade-colored Quartzite (SiO2)

Jadeite (Jade Ring)

NaAlSi2O6 (Sodium Aluminum Silicate)

Serpentine

Serpentine-group (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Green Calcite

Calcium Carbonate (CaCO3)

Epidote

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

Greenstone / Epidosite

Metamorphosed Mafic Igneous Rock (Epidote-Chlorite group)

Greenstone

Metabasalt

Greenstone (Diabase or Metabasalt)

Metamorphosed Mafic Igneous Rock

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Phyllite

Phyllite

Greenstone (Greywacke or Nephrite Jade variant)

Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities

Corundum (Ruby/Sapphire crystal)

Al2O3 (Aluminum Oxide)

Epidotite

Epidotite (Epidote content > 50%)

Banded Slate (Lithified Mudstone)

Low-grade Metamorphosed Mudstone / Slate

Gold in Quartz Ore

Hydrothermal Quartz with native Gold (Au)

Prehnite

Prehnite, Ca2Al(AlSi3O10)(OH)2

Emerald in Matrix (Quartz/Calcite)

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities