Chert (Iron-stained)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Category
Mineral, Specifically A Detrital Grain
Browse mineral, specifically a detrital grain specimens identified by the Rock Identifier community.
Granitic Pegmatite with Schorl
Granitic Pegmatite (Schorl: NaFe3Al6(Si6O18)(BO3)3(OH)3OH)
igneous
Pegmatite with Smoky Quartz and Feldspar
Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8)
igneous
Red Coral (Precious Coral)
Corallium rubrum (Calcium Carbonate, CaCO3)
sedimentary
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
sedimentary
Sandstone Pebble with Iron Staining
Clastic Sedimentary Rock (primarily Quartz with Fe2O3 oxides)
sedimentary
Fancy Jasper
Silicon Dioxide (SiO2) with mineral inclusions
sedimentary
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Mineral
Agate (specifically Lake Superior Agate style or Banded Chalcedony)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Green Calcite (often commercially called Green Onyx)
Calcium Carbonate (CaCO3)
Mineral
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Gastly (Trick or Trade Halloween Series)
Cellulose-carbonaceous composite (Lignocellulose laminated with pigmentary polymers)
Mineral (Synthetic - Paper and Ink Polymorph)
Rough Quartz in Pegmatite Matrix
Quartz (Silicon Dioxide - SiO2) in Granitic Pegmatite
igneous
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Banded Rock (likely Quartz-rich)
Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals
Mineral
Moqui Marble
Iron Oxide Concretion (Hematite/Goethite-cemented Sandstone)
sedimentary
Pegmatite (Granitic)
Granitic Pegmatite containing Quartz, Feldspar, and Tourmaline (Schorl)
igneous
Oolitic Limestone
Oolite (Sedimentary rock composed of CaCO3)
sedimentary
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Citrine (Yellow Quartz)
Silicon Dioxide (SiO2)
Mineral
Milky Quartz in Matrix
Silicon Dioxide (SiO2)
mineral
Amazonite
Potassium feldspar (Microcline) - K(AlSi3O8)
mineral
Quartzite
Quartzite (SiO2)
metamorphic
Rose Quartz
Silicon Dioxide (SiO2) with trace elements of Titanium, Iron, or Manganese
mineral
Moqui Marble (Shaman Stone)
Iron Oxide Concretion (Hematite/Goethite-encased Sandstone)
sedimentary
Chert (specifically tan/pink variety)
Silicon Dioxide (SiO2)
sedimentary
Aquamarine
Beryl (Be3Al2Si6O18), specifically the blue-green variety
Mineral
Iridescent Ammonite
Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)
sedimentary (fossilized)
Basalt
Extrusive mafic igneous rock
igneous
River Pebble (Siltstone/Mudstone)
Clastic sedimentary rock
sedimentary
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
metamorphic
Yellow Jasper
Silicon Dioxide (SiO2) with iron inclusions
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Garnet (specifically Almandine)
Almandine (Fe3Al2(SiO4)3)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Fluorite
Calcium Fluoride (CaF2)
mineral