Rock Identifier

Category

Organic Crystal (Mineraloid)

Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.

Chert (Tan/Buff Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Tan/Buff Chert)

Microcrystalline Quartz (SiO2)

Sandstone Concretion (Clastic sedimentary rock (primarily Quartz SiO2)) — sedimentary

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper/Mudstone) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Mudstone)

Silicon Dioxide (SiO2)

Chert (White Chert / Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Green variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Green variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Gray Chert) (Silicon Dioxide (Microcrystalline Quartz), SiO2) — sedimentary

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (Microcrystalline Quartz), SiO2

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper/Agate variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Moss Agate (Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)) — mineral

Moss Agate

Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (Nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2 - Quartz/Chalcedony replacement)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2 - Quartz/Chalcedony replacement)

Mineral / Fossil

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Chert (Flint) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Petrified Wood (Silicified Wood (primarily Chalcedony/Quartz, SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Pink Opal (Hydrated silicon dioxide (SiO2·nH2O) with inclusions) — mineral

Pink Opal

Hydrated silicon dioxide (SiO2·nH2O) with inclusions

Chert (Field Stone) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pyrite (Pyrite (Iron sulfide, FeS₂)) — Mineral

Pyrite

Pyrite (Iron sulfide, FeS₂)

Chert (specifically Jasper or Flint variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Jasper or Flint variant)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint or Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Smooth River Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Silicon Dioxide (SiO2)

Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Green Sandstone (Glauconitic Sandstone) — sedimentary

Green Sandstone

Glauconitic Sandstone

Chert / Flint (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Flint

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily SiO₂ - Silicon Dioxide)) — metamorphic

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Chert (Jasper/Iron-stained Quartzite) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Iron-stained Quartzite)

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Pearl (Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)) — mineral

Pearl

Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)

Chert (Yellow Jasper/Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood / Chalcedony (SiO2)) — mineral

Petrified Wood

Silicified Wood / Chalcedony (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert (specifically Jasper or Flint type) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Jasper or Flint type)

Microcrystalline Quartz (SiO2)

Ironstone Concretion (Ironstone Gourd) (Limonite/Goethite Concretion (FeOO(H))) — sedimentary

Ironstone Concretion (Ironstone Gourd)

Limonite/Goethite Concretion (FeOO(H))

Chert (specifically Yellow Jasper variety) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (specifically Yellow Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions

Chert (Gravel specimen) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Gravel specimen)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Chalcedony or Flint variation) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Chalcedony or Flint variation)

Microcrystalline Quartz (SiO2)

Lignite (Brown Coal) (Humic Lignite (Carbonaceous sedimentary rock)) — sedimentary

Lignite (Brown Coal)

Humic Lignite (Carbonaceous sedimentary rock)