Chalcedony (Agate)
Silicon Dioxide (SiO2)
mineral
Category
Mineral, Specifically A Rock Fragment
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Tiger's Eye (Brown/Dark variety)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
metamorphic
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
metamorphic
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
igneous
Schist
Mica Schist (Medium-grade Metamorphic Rock)
Metamorphic
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
metamorphic
Aragonite (variety 'Flos Ferri')
Aragonite (CaCO3)
Mineral
Chert (specifically Jasper/Flint pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood / Chalcedony (SiO2)
sedimentary
Vesicular Basalt (or Scoria)
Vesicular Basalt (Aphanitic-vesicular volcanic rock)
igneous
Agate
Agate (Silicon Dioxide, SiO2)
mineral
Basalt with Scoria
Amygdaloidal Basalt / Vesicular Basalt
igneous
Yellow Jasper
Silicon Dioxide with Iron inclusions (SiO2)
sedimentary
Emerald
Beryl (Be₃Al₂Si₆O₁₈), specifically the green variety colored by trace amounts of chromium or vanadium.
Mineral
Coquina
Bioclastic Limestone
sedimentary
Chert (specifically Yellow/Honey Jasper variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (specifically for Baltic amber; general formula C10H16O)
Mineraloid (Organic)
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Organic (Sedimentary-associated)
Shiva Lingam
Cryptocrystalline Quartz (Jasperiod Silicate with Iron Oxide inclusions)
sedimentary
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Gold-bearing Quartz with Iron Oxides
Quartz (SiO2) with Limonite/Goethite (FeO(OH)) and Pyrite (FeS2)
mineral
Garnet Schist
Almandine-Muscovite Schist
metamorphic
Garnet Schist
Almandine Garnet Schist (Fe3Al2(SiO4)3 in Schistose matrix)
metamorphic
Fluorite with Quartz coating
Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)
mineral
Fossiliferous Limestone
Calcite (CaCO3) with Bioclastic inclusions
sedimentary
Gold in Quartz Matrix
Native Gold (Au) with Quartz (SiO2) and Slate/Shale
mineral
Granite
Intrusive Felsic Igneous Rock
igneous
Mexican Crazy Lace Agate
Silicon Dioxide (SiO2) with iron and aluminum inclusions
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)
igneous
Banded Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Granite
Granite (Felsic Plutonic Rock)
igneous
Basalt with Quartz/Calcite Vein
Amygdaloidal Basalt (matrix) with Mineral Vein filling
igneous
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
igneous
Limestone (Flagstone)
Fossiliferous Limestone (CaCO3)
sedimentary
Note regarding baguette production (not a rock)
Digital text image - Somali language
not a rock
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
sedimentary
Shatter Cone
Impactite (Shatter Cone texture)
metamorphic
Amygdaloidal Basalt
Amygdaloidal Mafic Volcanic Rock
igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Calcite (Yellow/Orange variety - sometimes called Honey Calcite)
Calcite
Mineral