Rock Identifier

Category

Sedimentary (Secondary Classification: Cryptocrystalline Quartz)

Browse sedimentary (secondary classification: cryptocrystalline quartz) specimens identified by the Rock Identifier community.

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood (SiO2 - Silicon Dioxide)) — metamorphic

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2 - Silicon Dioxide)

Jasper with Hematite inclusions (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)) — sedimentary

Jasper with Hematite inclusions

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

Banded Agate (specifically Botryoidal/Orbicular Agate) (Silicon Dioxide (SiO2)) — Mineral (variety of Chalcedony/Quartz)

Banded Agate (specifically Botryoidal/Orbicular Agate)

Silicon Dioxide (SiO2)

Mineral (variety of Chalcedony/Quartz)

Moss Agate (Silicon dioxide (SiO2) with inclusions of hornblende or chlorite) — mineral

Moss Agate

Silicon dioxide (SiO2) with inclusions of hornblende or chlorite

Sandstone with Manganese Dendrites/Oxide coatings (Arenite with Pyrolusite and Romanechite (MnO2)) — sedimentary

Sandstone with Manganese Dendrites/Oxide coatings

Arenite with Pyrolusite and Romanechite (MnO2)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO2 - Silicon Dioxide)

Green Apophyllite and Stilbite on Quartz Cluster (Apophyllite-(K) (KCa4(Si8O20)(F,OH)·8H2O), Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O), Quartz (SiO2)) — Mineral

Green Apophyllite and Stilbite on Quartz Cluster

Apophyllite-(K) (KCa4(Si8O20)(F,OH)·8H2O), Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O), Quartz (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (Ca-rich Plagioclase, Pyroxene, and Olivine)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Ca-rich Plagioclase, Pyroxene, and Olivine)

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

Chert (Jasper/Opaline variety)

Silicon Dioxide (SiO2)

Milky Quartz / Rose Quartz fragment (Silicon Dioxide (SiO2)) — mineral

Milky Quartz / Rose Quartz fragment

Silicon Dioxide (SiO2)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Ocean Jasper (Orbicular Jasper (Silicon Dioxide with impurities), SiO2) — mineral

Ocean Jasper

Orbicular Jasper (Silicon Dioxide with impurities), SiO2

Native Copper (Native Copper (Cu)) — mineral

Native Copper

Native Copper (Cu)

Chrysoprase (Silicon dioxide with nickel impurities (SiO2 + Ni)) — mineral

Chrysoprase

Silicon dioxide with nickel impurities (SiO2 + Ni)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Argetine Blue Agate (Chalcendony variant) (Silicon Dioxide (SiO₂)) — mineral

Argetine Blue Agate (Chalcendony variant)

Silicon Dioxide (SiO₂)

Fossilized Wood (with Coal and Limonite) (Petrified Wood (Silicified or Carbonized Flora)) — sedimentary

Fossilized Wood (with Coal and Limonite)

Petrified Wood (Silicified or Carbonized Flora)

Iron Gossan (Limonite/Goethite) (Hydrated Iron Oxides (FeO(OH)·nH2O) from oxidation zones) — sedimentary

Iron Gossan (Limonite/Goethite)

Hydrated Iron Oxides (FeO(OH)·nH2O) from oxidation zones

Quartz (Silicon dioxide (SiO2)) — Mineral

Quartz

Silicon dioxide (SiO2)

Sandstone (River Rock) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (River Rock)

Arenite (composed primarily of SiO2)

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Chrysoprase (Chrysoprase (a variety of Chalcedony, SiO₂)) — Mineral

Chrysoprase

Chrysoprase (a variety of Chalcedony, SiO₂)

Blue Agate (Dyed Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Blue Agate (Dyed Chalcedony)

Silicon Dioxide (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Bloodstone (Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)) — Metamorphic Rock

Bloodstone

Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)

Metamorphic Rock

Chert or Flint (polished/water-worn) (Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.) — Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Chert or Flint (polished/water-worn)

Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.

Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Clear Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

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

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (likely) or a Quartzite Pebble (Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.) — Mineral, specifically a detrital grain

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Mineral, specifically a detrital grain

Petrified Wood (Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)) — Mineral/Fossil (Sedimentary context)

Petrified Wood

Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)

Mineral/Fossil (Sedimentary context)

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)

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

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Rhodolite Garnet (Magnesium Aluminum Silicate; formula: (Mg,Fe)3Al2(SiO4)3) — mineral

Rhodolite Garnet

Magnesium Aluminum Silicate; formula: (Mg,Fe)3Al2(SiO4)3

Sandstone (with potential mineral staining/concretions) (Arenite (SiO2 based)) — sedimentary

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Yellow Jasper (Silicon Dioxide (SiO2) with hydrated iron oxide impurities) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with hydrated iron oxide impurities

Vesicular Basalt (Basalt with secondary mineral infilling (Amygdaloidal Basalt)) — igneous

Vesicular Basalt

Basalt with secondary mineral infilling (Amygdaloidal Basalt)

Blue Quartz (Aventurine) (Silicon Dioxide (SiO2) with Crocidolite or Magnesio-riebeckite inclusions) — metamorphic

Blue Quartz (Aventurine)

Silicon Dioxide (SiO2) with Crocidolite or Magnesio-riebeckite inclusions

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Blue Lace Agate (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Blue Lace Agate (Tumbled)

Silicon Dioxide (SiO2)

Pyrite on Quartz (Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)) — mineral

Pyrite on Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Fluorite with Quartz coating (Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)) — mineral

Fluorite with Quartz coating

Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)