Basalt (River Pebble)
Basalt
Category
Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.
Basalt (River Pebble)
Basalt
Siltstone
Siltstone (primarily composed of quartz and clay minerals)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Conglomerate
Conglomerate (clastic sedimentary rock)
Amber (Cherry or Red variety)
Succinite (with various trace amounts of organic compounds)
Angelite
Anhydrite (Calcium Sulfate, CaSO4)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Glauconite
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2
Pumice
Vesicular volcanic glass (primarily SiO2 with Al2O3)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2 with various lithic fragments)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Riverstone Jasper (Chert variant)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide with iron impurities (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Quartz Pebble (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
Yellow Quartz (Citrinated Quartz)
Silicon Dioxide (SiO2)
Agate
Banded Chalcedony (SiO2 - Silicon Dioxide)
Conglomerate with Quartz Inclusions
Conglomerate (clastic sedimentary rock) with internal Quartz (SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Sandstone (Pebble)
Arenite (primarily SiO2)
Sandstone Concretion
Moqui Marble / Iron-oxide Concretion (SiO2 with Hematite/Goethite)
Basalt Pebble
Basalt (Aphanitic Mafic Igneous Rock)
Sandstone (likely with Quartz Veining)
Arenite (primarily SiO2)
Quartz
Silicon Dioxide (SiO2)
Magnetite / Hematite rich ore
Magnetite (Fe3O4) or Hematite (Fe2O3)
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with varying levels of hydration
Graphite
Graphite (C)
White Chalcedony (Agate)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Milky Variant)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Pyrite (Fool's Gold) Cube
Iron Sulfide (FeS2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Quartz
Quartz (SiO2 - Silicon Dioxide)