Likely quartz-rich mineral fragment
Quartz (SiO₂), possibly iron-stained or included quartz
Category
Browse mineral with metamorphic or sedimentary host specimens identified by the Rock Identifier community.
Likely quartz-rich mineral fragment
Quartz (SiO₂), possibly iron-stained or included quartz
Septarian Nodule
Septarian concretion (Calcite, Aragonite, and Limestone)
Druzy Quartz on Matrix
Silicon Dioxide (SiO2) on host rock
Quartz Geode
Silicon Dioxide (SiO2)
Sandstone with Quartz Vein
Arenite with Quartz (SiO2) Infilling
Turquoise
Hydrated copper and aluminum phosphate (CuAl6(PO4)4(OH)8·4H2O)
Schist (Diamond Drill Core)
Mica Schist
Garnet in Matrix (Eclogite)
Eclogite, featuring Almandine or Pyrope Garnet [X3Y2(SiO4)3]
Glauconitic Sandstone with possible Trace Fossil
Glauconitic Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)
Seam Agate
Agate (Banded variety of Chalcedony, SiO2)
Green Tourmaline (Verdelite)
Tourmaline Group; often Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) or Dravite (NaMg3Al6(BO3)3Si6O18(OH)4)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Quartz Geode in Chert/Limestone Matrix
Silicon Dioxide (SiO2) within Sedimentary Host Rock
Black Limestone with Calcite Veins
Carboniferous Limestone with Secondary Calcite Infill
Small rounded pebble, likely quartz-rich river stone
Indeterminate; likely quartz/chert-bearing lithic clast
Chalcedony / Agate with Botryoidal Quartz
Silicon Dioxide (SiO2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Quartz-rich pegmatite (possibly quartz–feldspar rock)
Granite pegmatite; chiefly quartz (SiO₂) with feldspar and minor mica/iron staining
Quartzite with Mafic Inclusion
Metamorphic Quartzite / Mafic Host Rock
Druzy Quartz (on Quartzite or Chert)
Silicon Dioxide (SiO2)
Pink Opal
Amorphous Hydrous Silica (SiO2·nH2O)
Boulder Opal
Amorphous Hydrous Silica (SiO2·nH2O)
Quartz Geode
Silicon Dioxide (SiO2) in a sedimentary or volcanic host
Tumbled blue-green chrysocolla (likely chrysocolla with quartz)
Chrysocolla, hydrated copper aluminum silicate; commonly intergrown with quartz, Cu₂H₂Si₂O₅(OH)₄
Quartz Geode
Silicon Dioxide (SiO2)
Greenstone
Greenschist / Meta-basalt
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Quartz Druzy
Crystalline Silicon Dioxide (SiO2)
Chalcedony (Agate/Carnelian)
Silicon Dioxide (SiO2)
Hypersthene (or Enstatite/Ferrosilite)
Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)
Sandstone Concretion
Septarian or Carbonate-cemented Sandstone Concretion
Limestone
Calcium Carbonate (CaCO3)
Schorl (Black Tourmaline)
NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Milky Quartz with Matrix
Silicon Dioxide (SiO2)
Smoky Quartz (Vein Quartz)
Quartz (Silicon Dioxide, SiO2)
Banded Agate (Polished Slice)
Chalcedony (cryptocrystalline Quartz), SiO2
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Iron-stained quartz (likely quartzite or quartz-rich rock)
Quartz, silicon dioxide (SiO₂), with iron-oxide staining
Orthoclase Feldspar (Salmon variety)
Orthoclase, KAlSi3O8