Amethyst
Silicon Dioxide with iron impurities (SiO2)
mineral
Category
The Purple Specimen Is A Mineral (Amethyst); The White Specimen Is A Sedimentary Rock (Limestone Or Marble).
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Mixed Tumbled Stones Collection
Mixed Silicates and Carbonates (Quartz, Amorphous Silica, Carbonates)
multiple
White Marble
Recrystallized Calcite (CaCO3) / Marble
metamorphic
Amethyst
Quartz (SiO2) variety
Mineral
Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe)
mineral
Amethyst (Quartz)
Amethyst (Silicon Dioxide with Iron impurities), SiO2
mineral
Quartzite
Quartzite (SiO2)
metamorphic
Gneiss (Metamorphic Cobble)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Amethyst (variety of Quartz)
SiO2 (Silicon Dioxide)
Mineral
Marble
Metamorphic Limestone (CaCO3)
metamorphic
Geodal Limestone / Calcite Druze
Calcium Carbonate (CaCO3)
sedimentary
Emerald with Matrix (Emerald in Mica Schist)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Amethyst (Geode)
Silicon Dioxide (SiO2) with iron impurities
mineral
White Marble
Recrystallized Calcite (CaCO3)
metamorphic
Sandstone (Ferruginous/Red Sandstone)
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
sedimentary
Chert (vuggy/nodular)
Microcrystalline Quartz (SiO2)
sedimentary
Calcite
Calcite (CaCO3)
Mineral
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Amethyst Lace Agate / Banded Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
mineral
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Mineral
Quartz (likely milky/gray variety)
Quartz (SiO₂)
Mineral
Quartz Geode
Silicon Dioxide (SiO2) in a Secondary Formation
sedimentary
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Chert (concretionary/nodular variant)
Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions
sedimentary
Marble
Recrystallized Calcite Rock (CaCO3)
metamorphic
Quartz Geode
Silicon Dioxide (SiO2) within a geode
sedimentary
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
mineral
Picasso Stone
Metamorphosed Calcium Carbonate (Limestone)
sedimentary
Chalcedony in Limestone Host Rock
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Mineral within Sedimentary Rock
Fossiliferous Chert (with Brachiopod or Mollusk fragments)
Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions
sedimentary
Smoky Quartz with Amethyst
Silicon Dioxide (SiO2)
mineral
Quartz (Druzy or Crystalline variety)
Silicon Dioxide (SiO2)
mineral
Quartz
Quartz (SiO2)
Mineral
Goniatite Fossil
Goniatitida (Order), fossilized in limestone/calcite (CaCO3)
sedimentary
Quartz (River Pebble)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Amethyst
Amethyst (Silicon Dioxide containing trace Iron impurities, SiO2)
mineral
Grooved Maun Ball (Maul/Hammerstone-like Concretion)
Calcareous/Ferruginous Concretion in Sandstone Matrix
sedimentary
Sandstone with Iron Concretion
Arenite with Limonite/Goethite Concretion
sedimentary
Amethyst (Faceted)
Silicon Dioxide with Iron impurities (SiO2)
mineral
Calcite (Banded Calcite / Onyx Marble)
Calcium Carbonate (CaCO3)
mineral