Metamorphic (Modified)

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite inclusions)

Gneiss or Schist

Gneiss or Mica Schist with Garnet

Garnet in Schist

Almandine Garnet in Mica-Schist (Fe3Al2(SiO4)3)

Magnetite-rich iron ore

Magnetite (Fe₃O₄), possibly massive magnetite/ironstone

Tumbled garnet (likely almandine)

Almandine garnet, iron-aluminum nesosilicate (Fe₃Al₂Si₃O₁₂)

Red corundum (ruby-colored polished crystal)

Corundum, aluminum oxide (Al₂O₃); red color is typically caused by chromium

Jadeite Jade

Jadeite (NaAlSi2O6)

Jade (likely Jadeite)

Jadeite (a pyroxene mineral) or Nephrite (a variety of amphibole mineral)

Quartz-rich rock fragment, possibly milky quartz

Quartz (SiO₂), likely a small vein-quartz or quartz-bearing rock fragment

Likely slate fragments

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

Schist

Mica Schist (Metamorphic Rock)

Garnet Schist

Almandine Garnet in Mica Schist (Fe3Al2(SiO4)3)

Epidote

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

Iron-stained weathered rock

Unknown

Quartz pebble

Silicon dioxide (SiO2)

Clear Quartz (Faceted) or Cubic Zirconia / Glass imitation

SiO2 (if Quartz), ZrO2 (if Cubic Zirconia)

Quartz with Chlorite inclusions

SiO2 with (Mg,Fe)3(Si,Al)4O10(OH)2⋅(Mg,Fe)3(OH)6

Aquamarine (Beryl)

Beryllium Aluminum Silicate - Be3Al2Si6O18

Sapphire

Corundum (Al2O3)

Sphalerite

Zinc Sulfide (ZnS)

Blue Apatite

Fluorapatite (Ca5(PO4)3(F,Cl,OH))

Blue Apatite

Ca5(PO4)3(F,Cl,OH)

Yellow Apatite

Fluorapatite (Ca5(PO4)3(F,Cl,OH))

Green Slate Pebble (Serpentine / Greenschist Pebble)

Greenschist / Low-grade Metamorphic Rock

Mica (Biotite or Phlogopite variety)

Phyllosilicate (complex mineral formula involving K, Mg, Fe, Al, Si, and O)

Quartz on Chlorite Schist

Chlorite Schist (Mg,Fe)3(Si,Al)4O10(OH)2 with Quartz (SiO2)

Quartzite

Quartzite

Lapis Lazuli

Lapis Lazuli (rock composed primarily of lazurite, calcite, and pyrite)

Ornamental ring with likely blue sapphire and diamonds

Blue corundum (sapphire), Al₂O₃; surrounding stones appear diamond, C, set in gold-colored metal

Tiger’s eye

Quartz (SiO₂), fibrous pseudomorph after crocidolite

Tumbled green aventurine (probable)

Quartz variety: aventurine quartz, SiO₂, colored commonly by fuchsite mica

Polished rhodonite

Rhodonite, manganese inosilicate (MnSiO₃)

Red gemstone ring, likely garnet or synthetic ruby

Possibly almandine garnet (Fe₃Al₂(SiO₄)₃) or corundum/ruby (Al₂O₃); image alone cannot distinguish

Rhodonite

Rhodonite (Manganese Iron Magnesium Calcium Silicate) - (Mn,Fe,Mg,Ca)SiO3

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)

Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)

Red faceted gemstone, likely synthetic ruby or red spinel

Ruby: corundum (Al₂O₃); spinel: MgAl₂O₄; visual identification alone is insufficient

Star ruby cabochon ring

Corundum, Al₂O₃ (ruby variety), displaying asterism

Tumbled quartz pebble

Quartz, silicon dioxide (SiO₂)

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Green aventurine quartz (probable)

Quartz, SiO₂, with fuchsite or other green mica inclusions

Rhodonite

Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3