Granite Cobble
Granite (Phaneritic Quartz-Feldspar Felsic Rock)
Category
Browse mineral specimen specimens identified by the Rock Identifier community.
Granite Cobble
Granite (Phaneritic Quartz-Feldspar Felsic Rock)
Quartzite Pebble
Quartzite (SiO2)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
Calcite
Calcite (CaCO₃)
Aventurine
Aventurine Quartz (SiO2 with inclusions)
Chert (Common Opal/Chalcedony)
Microcrystalline Quartz (SiO2)
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Diamond
Native Carbon (C)
Fossiliferous Sandstone (with Brachiopod or Bivalve mold)
Clastic Sedimentary Rock with Macrofossil Mold
Rose Quartz
Rose Quartz (SiO₂)
Tree Agate
Silicon Dioxide (SiO2) with Chlorite inclusions
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (and Chalcedony/Agate mixture)
Microcrystalline Quartz (SiO2)
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Amethyst
Silicon Dioxide with iron impurities (SiO2)
Yellow Quartz (Citrine or Quartz Crystal with Iron Inclusions)
Silicon Dioxide (SiO2)
Yellow Aventurine
Quartzite with inclusions (SiO2)
Quartzite
Quartzite (SiO2)
Pyrite (Fools Gold)
Iron Sulfide (FeS2)
Diamond (or Diamond Simulant)
Carbon (C)
Quartzite with Iron Inclusions
Quartzite (largely SiO2) with Hematite/Limonite staining (Fe2O3)
Diamond
Diamond (pure Carbon, C)
Serpentine (Serpentinite)
Serpentinite (complex silicate group including lizardite, chrysotile, and antigorite)
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
N/A - Man-made object (Jewelry Chain)
Antiqued or Oxidized Metal Chain (often Steel or Brass)
Banded Chert (or Banded Jasper)
Silicon Dioxide (SiO2) with Iron Oxide impurities (Hematite/Goethite)
Banded Agate (specifically Carnelian Agate slice)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
Slag (Industrial Glassy Byproduct)
Ferro-silicate Slag
River Pebble (Likely Quartzite or Chalcedony)
Silicon Dioxide (SiO2) - granular metamorphic variety
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Gold Flakes in Oil (Novelty Specimen)
Native Gold (Au)
Jasper with Quartz inclusion
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Goldstone (Red)
Aventurine Glass
Pumice or Tufa/Travertine
Pumice (if igneous) or Calcareous Tufa (if sedimentary)
Carborundum (Silicon Carbide)
Silicon Carbide (SiC)
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Granite (Pink/Potassium Feldspar Granite)
Felsic Plutonic Rock (Potassium Feldspar, Quartz, Mica, and Amphibole)
Quartz Geode
Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2)