Chert (Agatized)
Silicon dioxide (SiO2)
Category
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Chert (Agatized)
Silicon dioxide (SiO2)
Lapis Lazuli
Lazurite-dominant rock, (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2
Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
Amethyst Geode
Silicon Dioxide (SiO2) with iron impurities
Botryoidal Chalcedony (likely Chert or Agatized Coral)
Silicon Dioxide (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2)
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Lapis Lazuli
Complex rock primarily containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Chert (specifically Flint or Dark Chalcedony)
Silicon Dioxide (SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Banded Chert or Chert with Quartz Veins
Chert (SiO2)
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
Amethyst
SiO2 (Silicon Dioxide) - Purple variety of Quartz
Amethyst
SiO2 (Silicon Dioxide)
Chert (often called Jasper or River Siltstone)
Microcrystalline Quartz (SiO2)
Quartzite (River Cobble)
Quartzite (SiO2)
Sandstone (Pebble)
Arenite (primarily SiO2)
Amethyst
SiO2 (Silicon Dioxide with Iron impurities and natural radiation influence)
Citrine Quartz
SiO2 (Silicon Dioxide with Iron impurities)
Celestite (Celestine)
Strontium sulfate (SrSO4)
Amethyst Geode
Silicon Dioxide with impurities (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Amethyst and Ruby in Zoisite
Silicon Dioxide (SiO2) and Anyolite (Zoisite-Hornblende-Ruby mix)
Sandstone (likely Arkosic or Lithic)
Clastic Sedimentary Rock (SiO2 with accessory minerals)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Quartz (likely a form of massive or vein quartz)
Quartz (SiO₂)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Pink Anthracite Coal (dyed)
Anthracite Coal (Artificially Colored)
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
Grey Limestone Pebble
Limestone (Calcium Carbonate - CaCO3)
Calcite
Calcite (Calcium Carbonate, CaCO3)
Lapis Lazuli
Na8(Al6Si6O24)S2 (Lazurite is the primary constituent mineral)
Chert
Chert (Microcrystalline Silica, SiO2)
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Quartz (Druzy or Geode fragment)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Biogenic Calcium Carbonate (CaCO3)
Riverstone (Quartzite or Siltstone cobble)
Quartzite (primarily SiO2)
Chert Breccia (Yellow Jasper)
Silicon Dioxide (SiO2) - Brecciated Chert