Rock Identifier

Category

Organic Crystal (Mineraloid)

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

Chert (River Siltstone/Quartzite) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (River Siltstone/Quartzite)

Sedimentary Cryptocrystalline Quartz (SiO2)

Chert (often called Flint or Agate nodule) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Moss Agate (Crescent Moon Shape) (Silicon Dioxide (SiO2) with iron/manganese inclusions) — mineral

Moss Agate (Crescent Moon Shape)

Silicon Dioxide (SiO2) with iron/manganese inclusions

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

Red Coral (Precious Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

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

Fossiliferous Limestone

Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)

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

Chert (often referred to as Flint)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (and Jasper/Flint variety)

Cryptocrystalline Quartz (SiO2)

Chert (specifically Red Chert/Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Red Chert/Jasper variety)

Silicon Dioxide (SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (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)

Concretion (Septarian or Siderite Concretion) — sedimentary

Concretion

Septarian or Siderite Concretion

Green Moss Agate (Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Shungite (Fullerene-bearing carbonaceous rock) — mineral

Shungite

Fullerene-bearing carbonaceous rock

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

Chert / Flint

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Crinoid stem fragment) (Crinoidea (Phylum Echinodermata) in Calcite matrix) — fossil

Fossiliferous Limestone (Crinoid stem fragment)

Crinoidea (Phylum Echinodermata) in Calcite matrix

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert / Flint

Silicon Dioxide (SiO2)

Chert (varieties include Flint and Jasper) (Silicon dioxide (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon dioxide (SiO2)

Chert Nodule (Fossiliferous Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (Fossiliferous Chert)

Microcrystalline Quartz (SiO2)

Chert (Flint) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chert (varieties include Flint and Mudstone) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (varieties include Flint and Mudstone)

Microcrystalline Silica (SiO2)

Chert (Black Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Black Flint)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (Pebble)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (Pebble)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

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

Chert (Flint/Jasper)

Microcrystalline Quartz (SiO2)

Chert (Flint Nodules) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

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

Chert (specifically Gray Chert)

Silicon Dioxide (SiO2)

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

Chert / Flint (with Crinoid Stem Molds)

Microcrystalline Quartz (SiO2)