Rock Identifier

Category

Organic Crystal (Mineraloid)

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

Tufa (Limestone) (Calcareous Tufa (CaCO3)) — sedimentary

Tufa (Limestone)

Calcareous Tufa (CaCO3)

Chert (specifically Iron-stained or Jasperoid Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Iron-stained or Jasperoid Chert)

Microcrystalline Quartz (SiO2)

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

Chert (variations include Flint/Jasper)

Cryptocrystalline Quartz (SiO2)

Chert (Polished River Pebble) (Chert (SiO2)) — sedimentary

Chert (Polished River Pebble)

Chert (SiO2)

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

Chert (Nodule)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (often called Flint or Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Ferruginous Quartz (Silicon Dioxide (SiO2) with Hematite/Limonite impurities) — mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Glauconitic Sandstone (Greensand pebble) (Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand pebble)

Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)

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

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Chert (Commonly known as Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Commonly known as Flint)

Microcrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (Quartz, SiO2)) — metamorphic

Petrified Wood

Silicified wood (Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Chert (White-Tan variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Pink Opal (Common Opal) (Amorphous Hydrated Silica (SiO2·nH2O)) — mineral

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

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

Chert (Flint variety)

Silicon Dioxide (SiO2)

Chert / Flint Nodules (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Flint Nodules

Cryptocrystalline Quartz (SiO2)

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

Jasper

Jasper (Silicon Dioxide) - SiO2

Chert (Banded Variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Banded Variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and Flint) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (and Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Black Jasper (Black Stone / River Pebble) (Silicon Dioxide (SiO₂), Opaque variety of Chalcedony) — sedimentary

Black Jasper (Black Stone / River Pebble)

Silicon Dioxide (SiO₂), Opaque variety of Chalcedony

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

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Chert (Nodule) (Chert (primarily Microcrystalline Quartz - SiO2)) — sedimentary

Chert (Nodule)

Chert (primarily Microcrystalline Quartz - SiO2)

Chert (vuggy variety) (Microcrystalline silica (SiO2)) — sedimentary

Chert (vuggy variety)

Microcrystalline silica (SiO2)

Sandstone (with carbonaceous plant fragments) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

Chert (specifically River Stone / Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically River Stone / Jasper variety)

Microcrystalline Quartz (SiO2)

Chert (Nodule/Pebble) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

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

Chert (often called Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Agatized Chert / Chalcedony (Silicon Dioxide (SiO2)) — sedimentary

Agatized Chert / Chalcedony

Silicon Dioxide (SiO2)

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

Chert (Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)

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

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

Amber (Rough) (Amber (Fossilized Tree Resin, succinite)) — mineral

Amber (Rough)

Amber (Fossilized Tree Resin, succinite)

Jasper (specifically Polychrome or Desert Jasper) (Silicon Dioxide (SiO2) with iron oxide and other mineral impurities) — sedimentary (chemical/biological origin)

Jasper (specifically Polychrome or Desert Jasper)

Silicon Dioxide (SiO2) with iron oxide and other mineral impurities

sedimentary (chemical/biological origin)

Dragon Stone (Ohko Stone (Argillaceous sedimentary rock)) — sedimentary

Dragon Stone

Ohko Stone (Argillaceous sedimentary rock)

Sandstone (Arenicola (comprising mostly Quartz, SiO2)) — sedimentary

Sandstone

Arenicola (comprising mostly Quartz, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO₂)

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

Chert / Flint

Cryptocrystalline Quartz (SiO2)