Quartz (River Pebble)
Silicon Dioxide (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.
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)
sedimentary
Jasper (likely Lake Superior Jasper)
Jasper (Silicon Dioxide, SiO2)
sedimentary
Jasper (Iron-rich Microcrystalline Quartz)
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Biotite Schist
Biotite Schist (Rich in K(Mg,Fe)3AlSi3O10(OH)2)
metamorphic
Coal (Anthracite)
Anthracite (Carbon-based organic sedimentary/metamorphic rock)
metamorphic
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Blue Kyanite in Quartz
Kyanite (Al2SiO5)
mineral
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Devil's Toenail
Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)
sedimentary
Yellow Chert (River Stone)
Chert (SiO2)
sedimentary
Oolite (Ooids)
Oolitic Limestone (Principal mineral: Calcite, CaCO3)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Celestite (Celestine)
Strontium sulfate (SrSO4)
mineral
Epidote with Quartz/Feldspar
Epidote (Ca2(Al, Fe)3(SiO4)3(OH)) with associated minerals in a host rock
Mineral/Metamorphic rock
Yellow Quartz (Citrine/Quartzite Pebble)
Silicon Dioxide (SiO2)
mineral
Mookaite Jasper
Silicified Radiolarite (SiO2)
sedimentary
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Moqui Marble (Iron Oxide Concretion)
Iron Oxide Concretion (primarily Limonite/Hematite around a Sandstone center)
sedimentary
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Gold Ore
Native Gold in Quartz (Au)
mineral
Granite
Phaneritic Felsic Intrusive Igneous Rock
igneous
Pink Quartzite
Quartzite (primarily SiO2)
metamorphic
Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color
Silicon Dioxide (SiO2), a variety of Chalcedony
Sedimentary Rock
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Note regarding baguette production (not a rock)
Digital text image - Somali language
not a rock
Ferruginous Sandstone (with ripple marks)
Arenite with Iron-Oxide (Fe2O3) cement
sedimentary
River Jasper (Chert/Chalcedony mix)
Silicon Dioxide (SiO2) with iron oxide and chlorite inclusions
sedimentary
Granite
Phaneritic intrusive igneous rock (approx. 70 percent SiO2)
igneous
Turritella Agate (Elimia Agate)
Silicified Elimia tenera (formerly misidentified as Turritella)
sedimentary (silicified fossiliferous chalcedony)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide - SiO2)
mineral
Fossilized Favosites (Honeycomb Coral)
Favosites (extinct genus of tabulate coral)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz (Crystal/Druzy Quartz)
Quartz (SiO₂)
Mineral
Granite Cobble (River Stone)
Felsic intrusive igneous rock (composition: Quartz, Feldspar, Mica)
igneous