Gneiss (specifically a water-worn pebble)
Gneiss
Category
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Gneiss (specifically a water-worn pebble)
Gneiss
Carnelian
Carnelian (Microcrystalline Quartz, SiO2 with Fe2O3 impurities)
Yellow Jasper
Chalcedony (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Jasper
Jasper (Silicon Dioxide, SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Chert with Asphaltum (or Tar)
Silica (SiO2) with natural Bitumen/Asphaltum
Orange Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Fossiliferous Limestone
Calcite (CaCO3) Rich Bio-sedimentary Rock
Unakite
Unakite (Epidotized Granite)
Quartzite (River Stone)
Quartzite (mainly SiO2 with iron oxide staining)
Botryoidal Agate / Chalcedony Geode
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Kyanite
Kyanite (Al2SiO5)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Chert (varietal Flint)
Silicon Dioxide (SiO2)
Chert (Commonly known as Flint or River Pebble)
Microcrystalline Quartz (SiO2)
Carnelian
SiO2 (Microcrystalline Quartz / Chalcedony)
Fossilized Brachiopod
Brachiopoda (Class Rhynchonellata or Spiriferida)
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Flint (Chert)
Cryptocrystalline Quartz (SiO2)
Geode (Unopened)
Silica-rich concretion (SiO2)
Graphite
Graphite (Native Carbon, C)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Banded Agate
Agate (Silicon Dioxide, SiO2)
Blue Chalcedony
Chalcedony (SiO2)
Gold
Native Gold (Au)
Quartz Druzy on Geode Fragment
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Turritella Agate (Calligrapher Stone)
Silicified Elimia tenera (Chalcedony/Quartz)
Druzy Quartz on Limestone
Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)