Crystal

Titanium Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Blue calcite

Calcite (CaCO₃)

Rose quartz

Quartz, silicon dioxide (SiO₂)

Pink quartz crystal cluster

Quartz (silicon dioxide, SiO₂), likely rose quartz or pale amethyst

Amethyst cluster

Quartz, SiO₂, violet variety (amethyst)

Quartz crystal cluster with possible chlorite inclusions

Quartz, silicon dioxide (SiO₂), likely with minor chlorite or iron-oxide staining

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Amethyst crystal cluster

Amethyst, purple variety of quartz (SiO₂)

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

Magnetite (Octahedral Crystal)

Magnetite (Fe3O4)

Raw quartz fragment

Quartz (SiO₂), likely milky or included quartz

Polished blue chalcedony (likely blue agate)

Cryptocrystalline quartz, SiO₂; chalcedony variety

Tumbled Rose Quartz

Quartz (SiO2)

Clear Quartz Cluster

Silicon Dioxide (SiO2)

Ferruginous Quartz

Quartz (Silicon Dioxide) with Iron Inclusion (SiO2 + Fe2O3)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Quartz (Silicon Dioxide - SiO2)

Pyrite (likely)

Pyrite, FeS₂

Rough Emerald Crystals

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Quartz crystal cluster

Quartz (silicon dioxide, SiO₂), likely milky or included quartz

Druzy Quartz on Sandstone

Silicon Dioxide (SiO2) on Sedimentary Host Rock

Clear quartz (likely rough quartz crystal)

Quartz, silicon dioxide (SiO₂)

Clear Quartz Crystal

Quartz (Silicon Dioxide - SiO2)

Faceted Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions

Possible black tourmaline (schorl)

Schorl, NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Tumbled green chalcedony (likely chrysoprase)

Chalcedony, microcrystalline quartz (SiO₂); green color may be from nickel-bearing chrysoprase

Smoky Quartz in Matrix

Silicon dioxide (SiO2) within Pegmatite/Gneiss

Goldstone (likely blue-free synthetic goldstone pendant)

Synthetic aventurine glass; silica glass with dispersed metallic copper crystals

Quartz geode

Quartz (SiO₂), likely chalcedony-lined geode with drusy quartz crystals

Pyrite in Matrix (Quartz/Schist)

Iron Sulfide (FeS2)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Blue kyanite crystal

Kyanite, Al₂SiO₅

Quartz Crystal Fragment

Quartz (Silicon Dioxide, SiO2)

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Quartz (Crystal Fragment)

Silicon Dioxide (SiO2)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Hemimorphite on Limonite Gossan

Hemimorphite (Zn4Si2O7(OH)2·H2O) on Limonite matrix

Celestine (Celestite)

Strontium sulfate (SrSO4)