Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Category
Browse sedimentary or igneous fragment specimens identified by the Rock Identifier community.
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Opal
Hydrated Silica (SiO2·nH2O)
Druzy Quartz (on Geode Fragment)
Silicon Dioxide (SiO2)
Granite Pebble
Granite (composed primarily of Quartz, Feldspar, and Mica)
Red Garnet (likely Almandine or Pyrope)
Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)
Milky Quartz
Silicon Dioxide (SiO2)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Pebble
Clast (specifically a granule or small pebble)
Sandstone-based Concrete Fragment
Cementitious Composite with Sedimentary Aggregate
Gneiss
Gneiss
Quartz Pebble
Silicon Dioxide (SiO2)
Granite
Granite (Felsic Plutonic Rock)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Cloudy variety)
Silicon Dioxide (SiO2)
Quartz Geode / Druzy Quartz
Silicon Dioxide (SiO2)
Agate (Fortification Agate)
Banded Chalcedony (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Unidentifiable Specimen
Undetermined
Coquina or Fossilized Shell Fragment
Calcium Carbonate (CaCO3) / Biogenic Limestone
Coarse Sand or Fine Gravel
Detrital Sedimentary Fragments (mostly SiO2)
Sandstone Concretion
Ferruginous Sandstone Concretion
Iron Meteorite (Campo del Cielo)
Iron Meteorite, Group IAB (FeNi Alloy: Kamacite and Taenite)
Amethyst
Amethyst (SiO2 - Silicon Dioxide with iron impurities)
Quartz (Druzy or Geode fragment)
Silicon Dioxide (SiO2)
Quartz (with inclusions / Sandstone fragment)
Silicon Dioxide (SiO2)
Crushed Limestone Aggregate
Limestone (Calcium Carbonate, CaCO3)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Quartz (Microcrystalline variety)
Silicon Dioxide (SiO2)
Seashell Fragment (Aragonite/Calcite)
Calcium Carbonate (CaCO3) - Shell fragment
Quartz (Chert/Chalcedony variety)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
Quartz / Common Gravel
Silicon Dioxide (SiO2)
Chert (Arrowhead Preform)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Fossiliferous Shale
Laminated Mudrock with plant fossils
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Chalcedony (Agate/Seashell replacement)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Granite fragment
Phaneritic Igneous Rock (Granitic composition)
Limonitic Sandstone with Inclusion
Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)