Gneiss (with Quartzite and Biotite)
Gneiss containing SiO2 (Quartz), K(Mg,Fe)3AlSi3O10(OH)2 (Biotite), and (K,Na,Ca)AlSi3O8 (Feldspar)
Category
Browse mineralological specimen specimens identified by the Rock Identifier community.
Gneiss (with Quartzite and Biotite)
Gneiss containing SiO2 (Quartz), K(Mg,Fe)3AlSi3O10(OH)2 (Biotite), and (K,Na,Ca)AlSi3O8 (Feldspar)
Quartzite Pebble
Quartzite (SiO2)
Selenite (Satin Spar)
Gypsum (CaSO4·2H2O)
Sandstone (likely Quartzose)
Clastic sedimentary rock (SiO2 primary)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
River Cobble (Phyllite or Quartzite)
Metasedimentary Rock (often containing SiO2 or KAl2(AlSi3O10)(OH)2)
Basalt with Vesicular Surface
Basalt (Mafic Extrusive)
Granite
Felsic Plutonic Rock (primarily SiO2)
Coarse-grained Granite
Granitoid (KAlSi3O8 + SiO2 + NaAlSi3O8)
Sandstone
Clastic sedimentary rock (primarily Quartz and Feldspar)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Basalt River Pebble
Basalt
Diorite (River Pebble)
Intermediate plutonic igneous rock
Yellow Quartzite (River Pebble)
Quartzite (primarily SiO2)
Peridotite (Dunite)
Peridotite (mostly Olivine: (Mg,Fe)2SiO4)
Chert (Gravel Bit)
Microcrystalline silica (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Limestone (specifically Crushed Limestone/Calcictic)
Calcium Carbonate (CaCO3)
Acrylic or Resin (Synthetic Imitation)
Polymethyl Methacrylate (PMMA) or Polyepoxide
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
Chert (with Iron Staining)
Silicon Dioxide (SiO2)
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Quartz (Orangey-white variety)
Silicon Dioxide (SiO2)
Yellow Quartzite Pebble
Quartzite (primarily SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with high iron inclusion
Chert (containing Iron Oxide spots)
Microcrystalline Quartz (SiO2)
Green Calcite (Onyx Marble)
Calcium Carbonate (CaCO3)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Chert (Pebble)
Chert (Microcrystalline Quartz, SiO2)
Quartz (Beach Pebble)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2-rich)
Basalt (Water-worn Pebble)
Mafic Volcanic Rock (High in Fe and Mg)
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Yellow Chert (River Stone/Pebble)
Chert (Cryptocrystalline Quartz, SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (with iron oxide cement, Fe2O3)
Granite Pebble (River Rock)
Granite (composed primarily of Quartz, Feldspar, and Mica)