Garnet (likely Almandine, Pyrope, or a blend)
Garnet group minerals: X3Y2(SiO4)3, where X and Y represent various metal ions (e.g., Almandine: Fe3Al2(SiO4)3, Pyrope: Mg3Al2(SiO4)3)
Category
Browse metamorphic (localized) or sedimentary specimens identified by the Rock Identifier community.
Garnet (likely Almandine, Pyrope, or a blend)
Garnet group minerals: X3Y2(SiO4)3, where X and Y represent various metal ions (e.g., Almandine: Fe3Al2(SiO4)3, Pyrope: Mg3Al2(SiO4)3)
Quartz (likely)
Quartz (SiO2 - Silicon Dioxide)
Hematite
Hematite (Fe2O3)
Sandstone
Arenite
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Agate (various color varieties)
SiO₂ (Silicon Dioxide)
Quartz (Float/Abraded)
Quartz (SiO₂)
Pyrite
Iron Pyrite (FeS2)
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Opal
Hydrated Silica (SiO2·nH2O)
Quartz
Silicon Dioxide (SiO2)
Botryoidal Quartz
Silicon Dioxide (SiO2)
White Chalcedony (Agate)
Silicon Dioxide (SiO2)
Carnelian (Carnelian Agate)
Silicon dioxide (SiO2) - a variety of Chalcedony
Blue Chalcedony
Silicon Dioxide (SiO2)
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Agate (Crazy Lace or Eye Agate)
Silicon Dioxide (SiO2)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
Quartz
Quartz (SiO₂)
Bauxite (Concretionary)
Bauxite (Al(OH)3, AlO(OH))
Jasper
Silicon dioxide (SiO2) with iron oxide impurities
Jasper
Silicon Dioxide (SiO2)
Carnelian
Carnelian (SiO2)
Jasper (Green Jasper / Chert)
Silicon Dioxide (SiO2) with iron/clay inclusions
Green Chalcedony
Silicon Dioxide (SiO2) with trace minerals
Amethyst (Geode/Druzy)
Silicon Dioxide (SiO2) with iron impurities
Yellow Chalcedony (Agate/Chert)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chalcedony / Agate
Silicon Dioxide (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2)
Chalcedony (Agate/Carnelian type)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (pronounced 'nice')
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Smoky Quartz
SiO2 (Silicon Dioxide)
Amethyst
Quartz (SiO2) variety
Calcite
Calcite (CaCO 3)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with Iron Oxide inclusions
Calcite with Quartz coating
Calcium Carbonate (CaCO3) with Silicon Dioxide (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2)
Chalcedony (Agate/Carnelian variety)
Cryptocrystalline Quartz (SiO2)
Quartz Geode
Crystalline Quartz (Silicon Dioxide, SiO2)