River Rock / Stream Pebble
Fluvial Clast / Rounded Sedimentary Particle
Category
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
River Rock / Stream Pebble
Fluvial Clast / Rounded Sedimentary Particle
Sandstone
Arenite (SiO2 based with various mineral cements)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Diamond
Diamond (C)
Diamond (Rough)
Diamond (C)
Grey Slate
Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)
Vesicular Basalt
Mafic Volcanic Rock (Basalt)
Red Jasper (with Quartz Veins)
Jasper (var. chert, SiO₂)
Granite
Granite (felsic intrusive igneous rock)
Riverstone Quartzite (Water-worn Siltstone/Quartzite)
Metamorphosed Quartz-rich Arenite (SiO2)
Granite (specifically Rapakivi Granite)
Phaneritic Felsic Igneous Rock (Granite)
Diamond
Diamond (C)
Popcorn
Zea mays everta (P. Wilson) (Botanical name for the corn variety)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Sandstone (Greywacke/Lithic Sandstone)
Arenite / Lithic Sandstone
Amazonite
KAlSi3O8 (Potassium Feldspar, variety of Microcline)
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Schist
Mica Schist (primarily Muscovite [KAl2(AlSi3O10)(OH)2] or Biotite)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Ironstone (likely Limonite or Goethite)
Ferruginous sedimentary rock (FeO(OH)·nH2O)
Ruby in Zoisite
Ruby (Corundum, Al2O3) in Zoisite (Calcium aluminum silicate hydroxide, Ca2Al3(SiO4)3(OH)) with some Hornblende
Granite
Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)
Ironstone with Pyrite
Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss (Metamorphic rock of variable composition, typically SiO2 rich)
Schist
Mica Schist (Medium-grade metamorphic rock)
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
Kyanite (Blue Kyanite)
Kyanite (Al2SiO5)
Black Chert
Chert (microcrystalline quartz)
Lapis Lazuli
Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
Titanium Coated Kyanite (Aura Kyanite)
Aluminosilicate (Al2SiO5) with a Titanium-Niobium vacuum-deposited coating
Amazonite
Amazonite (KAlSi3O8, a variety of Microcline)
Schist
Schist (various mineral compositions)
Diorite
Diorite (Intermediate intrusive igneous rock)
River Cobble (Basaltic/Andesitic)
Mafic Igneous Porphyritic Rock
Granite (Weathered)
Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)
Nuummite
Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Mica (Biotite and Muscovite) in Matrix
Potassium aluminum silicate with iron/magnesium (KAl2(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(F,OH)2)
Tufa
Calcareous Tufa (CaCO3)
Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)
Chalcedony (SiO₂)