River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
Category
Browse sedimentary and metamorphic minerals specimens identified by the Rock Identifier community.
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
Banded Gneiss (River Cobble)
Gneiss (a high-grade metamorphic rock)
Schist
Mica Schist
Osumilite in Granite Matrix
(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30
Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)
Quartz (SiO₂)
Sand (Construction Grade)
Unconsolidated siliciclastic sediment (primarily SiO2)
Pyrite
Iron Sulfide (FeS2)
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Petrified Wood
Silicified Wood (SiO2)
Nephrite Jade
Nephrite (a variety of the mineral actinolite within the amphibole group); Chemical Formula: Ca2(Mg,Fe)5Si8O22(OH)2
Quartz
Quartz (SiO2 - Silicon Dioxide)
Pyrite
Pyrite (FeS₂)
Kyanite
Kyanite (Al2SiO5)
Petrified Wood
Silicified Wood (SiO2)
Green Aventurine
Aventurine Quartz (SiO2 with fuchsite inclusions)
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Greenschist
Chlorite schist
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
Pyrite
Pyrite (Iron Disulfide), FeS2
Fluorite
Calcium Fluoride (CaF2)
Petrified Wood
Silicified Wood (SiO2)
Aventurine Quartz
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
Greenschist (Greenstone)
Chlorite Schist / Greenschist Facies Rock
Gneiss
Gneiss (Metamorphic rock of variable composition, typically SiO2 rich)
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Blue Quartz (potentially Dumortierite-included)
Silicon Dioxide (SiO2) with inclusions
Peacock Ore (Bornite/Chalcopyrite)
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Greenstone
Greenschist (containing chlorite, epidote, and actinolite)
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Greenstone / Chert
Cryptocrystalline Quartz (SiO2) or Altered Basalt
Sapphirine in Matrix
Sapphirine (Mg,Al)8(Al,Si)6O20
Quartz / Clear Quartz
Silicon Dioxide (SiO2)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Mn2+SiO3)
Yellow Aventurine (Yellow Quartzite)
Silicon Dioxide (SiO2) with inclusions
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Apatite
Apatite group mineral (e.g., Fluorapatite - Ca5(PO4)3F, Chlorapatite - Ca5(PO4)3Cl, Hydroxylapatite - Ca5(PO4)3(OH))
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Quartz (specifically Milky Quartz/Quartzite)
Silicon Dioxide (SiO2)