Anthracite Coal
Anthracite (Carbon-rich metamorphic rock)
Category
Browse sedimentary rock (altered) specimens identified by the Rock Identifier community.
Anthracite Coal
Anthracite (Carbon-rich metamorphic rock)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (Formula: (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Bumblebee Jasper
Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)
Caliche (with Lichen Cover)
Calcium carbonate-cemented soil layer (CaCO3)
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (containing Flint and Calcareous inclusions)
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) impurities
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Marble
Recrystallized Calcite (CaCO3)
Coquina
Coquina (a type of limestone)
Chert (Yellow/Brown variety)
Chert (SiO2)
Limestone
Calcium carbonate ( преимущественно CaCO3)
Chert (Field Stone)
Chert (SiO2)
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Chert (Flint variety)
Chert (SiO2)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Chert (Quartz Variety)
Silicon Dioxide (SiO2)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
Agate (Carnelian-Blue Agate mix)
Silicon Dioxide (SiO2)
Basalt River Stone
Basalt (Aphanitic Mafic Igneous Rock)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Thunderegg (Ate Agate/Jasper Geode)
Silicon Dioxide (SiO2) within Rhyolite/Perlite matrix
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz (various varieties)
SiO₂ (Silicon Dioxide)
Native Copper within Host Rock
Native Copper (Cu)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Terrazzo (Man-made Composite)
Cementitious or Resin-bound Lithic Composite
Glacial Erratic (Sandstone/Quartzite)
Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)
Banded Onyx (Calcite Marble)
Calcite (CaCO3) - Trap-rock or Cave Onyx
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Rough Garnet in Matrix
Almandine Garnet (Fe3Al2Si3O12)
Chert (varietal known as Jasper or Flint)
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (ferruginous sandstone)
Gneiss with Quartz Veining
Gneiss (High-grade regional metamorphic rock)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Fossiliferous Limestone (with Coralline Inclusions)
Calcium Carbonate (CaCO3)
Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert / River Pebble
Microcrystalline Silica (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified wood (primarily SiO2)