Rock Identifier

Category

Organic Crystal (Mineraloid)

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

Chert (often referred to as Flint) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (often referred to as Flint)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Chert (often called Flint when in chalk or limestone) (Silicon Dioxide (SiO₂)) — sedimentary

Chert (often called Flint when in chalk or limestone)

Silicon Dioxide (SiO₂)

Tree Agate (Dendritic Agate (Silicon Dioxide, SiO2)) — mineral

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Chert (variations include Flint/Jasper) (Chert (SiO2)) — sedimentary

Chert (variations include Flint/Jasper)

Chert (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

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

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

Chert (often called Flint for darker varieties) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (often called Flint for darker varieties)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Pyrite Geode (Sparkling Druzy) (Iron Sulfide (FeS2) in Sedimentary Nodule) — mineral

Pyrite Geode (Sparkling Druzy)

Iron Sulfide (FeS2) in Sedimentary Nodule

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Yellow Jasper/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (Quartz, Chalcedony, or Opal)) — sedimentary

Petrified Wood

Silicified wood (Quartz, Chalcedony, or Opal)

Geode (unopened) (Chert / Chalcedony Geode (SiO2)) — sedimentary

Geode (unopened)

Chert / Chalcedony Geode (SiO2)

Amber (Succinite (a common variety of fossilized resin)) — mineral

Amber

Succinite (a common variety of fossilized resin)

Pearl (Aragonite (CaCO3 with conchiolin)) — mineral

Pearl

Aragonite (CaCO3 with conchiolin)

Red Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (Jasper variation) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper variation)

Microcrystalline Quartz (SiO2)

Chert (Iron-stained) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Iron-stained)

Chert (Silicon Dioxide, SiO2)

Amber with inclusion (Amber (Fossilized Tree Resin)) — mineral

Amber with inclusion

Amber (Fossilized Tree Resin)

Amber (Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O) — mineral

Amber

Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxide

Chert (Chert (SiO2)) — sedimentary

Chert

Chert (SiO2)

Chalcedony (or a variety of Chalcedony, likely Agate or Jasper) (Chalcedony (SiO₂)) — Mineral (or mineraloid if microcrystalline)

Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)

Chalcedony (SiO₂)

Mineral (or mineraloid if microcrystalline)

Glauconitic Sandstone (Glauconitic Quartz Arenite) — sedimentary

Glauconitic Sandstone

Glauconitic Quartz Arenite

Red Coral (Precious Coral) (Corallium rubrum (Calcium Carbonate, CaCO3)) — sedimentary

Red Coral (Precious Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

Chert (Chert / Flint) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (Chert / Flint)

Silicon dioxide (SiO2) - Microcrystalline quartz

Chert (with Limestone matrix) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Limestone matrix)

Microcrystalline Quartz (SiO2)

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

Moss Agate

Agate (Silicon Dioxide, SiO2) with dendritic inclusions

Amber (Rough Baltics/Beach Specimen) (Succinicum (Organic Gemstone - Fossilized Resin)) — mineral

Amber (Rough Baltics/Beach Specimen)

Succinicum (Organic Gemstone - Fossilized Resin)

Chert / Flint (with Crinoid Stem Molds) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Flint (with Crinoid Stem Molds)

Microcrystalline Quartz (SiO2)

Chert (specifically Gray Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Gray Chert)

Silicon Dioxide (SiO2)

Chert (Limestone-based) (Silicon dioxide (SiO2)) — sedimentary

Chert (Limestone-based)

Silicon dioxide (SiO2)

Chert (Arrowhead Preform or Flake) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead Preform or Flake)

Microcrystalline Quartz (SiO2)

Fossilized Coral (Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)) — sedimentary

Fossilized Coral

Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)

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

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Chert (or Flint) (Chert (Sedimentary Cryptocrystalline Sio2)) — sedimentary

Chert (or Flint)

Chert (Sedimentary Cryptocrystalline Sio2)

Chert (often called Flint or Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)