Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
Category
Browse rock specimens identified by the Rock Identifier community.
Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Unakite
Unakite (Epidotized Granite)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Unakite
Unakite (altered granitic rock: SiO2 + Ca2(Al,Fe)3(SiO4)3(OH))
Diorite (Dalmatian Stone)
Phaneritic Plutonic Diorite
Basalt
Basalt
Basalt (River Pebble)
Extrusive Magic Igneous Rock (Mainly Plagioclase and Pyroxene)
Basalt (River Cobble)
Basalt (Mafic Extrusive Igneous Rock)
Unakite
Epidotized Granite
Unakite
Epidotized Granite (Fe, Ca, Al silicate + KAlSi3O8)
Unakite
Unakite (Epidotized Granite)
Serpentine
Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Sandstone
Arenite
Basalt
Basalt
Unakite
Epidotized Granite
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Quartz (River Siltstone Quartzite Pebble)
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite
Sandstone
Arenite (SiO2 primarily)
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Lapis Lazuli
Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
Fossilized Favosites (Honeycomb Coral)
Favosites (extinct genus of tabulate coral)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Granite
Phaneritic Felsic Igneous Rock
Quartz-veined Siltstone/Greywacke
Clastic Sedimentary Rock with Quartz Infill (SiO2 vein)
Quartz (Milky/Granular)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Terrazzo (with Marble and Granite fragments)
Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates
Rose Quartz
Silicon Dioxide (SiO2) with trace Titanium or Manganese
Agate (Crazy Lace or Eye Agate)
Silicon Dioxide (SiO2)
Quartz Geode (with possible Manganese or Goethite coating)
Silicon Dioxide (SiO2)
Ironstone Concretion
Siderite or Ferruginous Concretion (FeCO3 or Iron Oxides)
Fossilized Coral
Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Matrix
Fossil Shell in Sedimentary Matrix
Bivalvia (fossil) in Calcium Carbonate Matrix
Shale
Shale (composition varies: primarily clay minerals and quartz)
Granite
Granite
Sandstone
Clastic sedimentary rock (primarily SiO2)
Basalt
Basalt
Granodiorite (foreground) and Rose Quartz (background)
Granodiorite / Quartz (SiO2)