Orange Calcite (Carved as a Horned Skull)
Calcium Carbonate (CaCO3)
Category
Browse mineral (sedimentary context) specimens identified by the Rock Identifier community.
Orange Calcite (Carved as a Horned Skull)
Calcium Carbonate (CaCO3)
Chalcedony
Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (SiO2 based)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
Petrified Wood
Silicified Wood (SiO2)
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
Sand (Construction Grade)
Unconsolidated siliciclastic sediment (primarily SiO2)
Chert (Flint variety)
Silicon Dioxide (SiO2)
Sandstone
Quartz Arenite (a type of sandstone composed of more than 90% quartz)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz pebble)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Druzy Quartz (on Quartzite or Chert)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Herkimer Diamond
Quartz (Silica - SiO2)
Milky Quartz (Druzy Geode fragment)
Silicon Dioxide (SiO2)
Black Opal
Hydrated Silica (SiO2·nH2O)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Orange Calcite with Siderite/Iron Oxide Coating
Calcium Carbonate (CaCO3)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities
Amethyst with Marcasite accents
Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)
Graphite
Graphite (Native Carbon, C)
Conglomerate
Conglomerate (clastic sedimentary rock)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood / Chalcedony (SiO2)
Jasper Beach Pebble
Silicon Dioxide (SiO2) - Macro-crystalline Quartz
Chert (Nodule)
Silicon Dioxide (SiO2)
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Green Aventurine (Green Quartzite)
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
Hag Stone
Perforated Sedimentary Rock (typically Limestone or Sandstone)
Gneiss (likely)
Gneiss
Pyrite
Pyrite (FeS2)
Marble
Recrystallized Calcite (CaCO3)
Gneiss
Gneiss (Metamorphic high-grade)
Chert (Flint) with Glauconite
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss (a type of metamorphic rock)
Amber
Succinite (Resinous fossilized tree sap)
Red Jasper
Silicon dioxide with hematite impurities (SiO2 + Fe2O3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Iron Oxide inclusions (Fe2O3)
Chalcedony (Agate)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)