Rock Identifier

Category

Amorphous Solid

Browse amorphous solid specimens identified by the Rock Identifier community.

Learn about Amorphous Solid in the encyclopedia

Tripolite

Rainbow Obsidian

Rainbow Obsidian

Oil Shale

Apache Tears

Grandite Garnet

Geyserite

Gold Sheen Obsidian

Black Obsidian

Diatomaceous Earth

Shungite

Flame Obsidian

Smoky Obsidian

Ironstone Concretion (Moqui Marble) (Ironstone concretion (Fe2O3 with a sandstone core)) — sedimentary

Ironstone Concretion (Moqui Marble)

Ironstone concretion (Fe2O3 with a sandstone core)

Native Copper in Basalt (Cu-element in Mafic Volcanic Rock (Basalt)) — igneous

Native Copper in Basalt

Cu-element in Mafic Volcanic Rock (Basalt)

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

Petrified Wood

Silicified wood (Quartz, SiO2)

Pumice (Pumice (Vesicular Volcanic Glass)) — igneous

Pumice

Pumice (Vesicular Volcanic Glass)

Tumbled amber-like inclusion (Likely amber (fossilized tree resin; complex polymer), but identification is uncertain from the image) — gemstone

Tumbled amber-like inclusion

Likely amber (fossilized tree resin; complex polymer), but identification is uncertain from the image

Obsidian (black volcanic glass) (Obsidian; predominantly rhyolitic volcanic glass, mainly SiO₂ with minor feldspar, quartz, and iron oxides) — igneous

Obsidian (black volcanic glass)

Obsidian; predominantly rhyolitic volcanic glass, mainly SiO₂ with minor feldspar, quartz, and iron oxides

Amber (likely rough amber) (Fossilized plant resin; predominantly polymerized terpenoid resin (succinite if Baltic-type)) — gemstone

Amber (likely rough amber)

Fossilized plant resin; predominantly polymerized terpenoid resin (succinite if Baltic-type)

Obsidian arrowhead flakes (Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–75% SiO₂)) — igneous

Obsidian arrowhead flakes

Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–75% SiO₂)

Sandstone (Sedimentary Clastic Rock (Quartz Arenite)) — sedimentary

Sandstone

Sedimentary Clastic Rock (Quartz Arenite)

Pumice (Pumice (Volcanic glass / Silicic extrusive rock)) — igneous

Pumice

Pumice (Volcanic glass / Silicic extrusive rock)

Pumice (Pumice (Vesicular Felsic Igneous Rock)) — igneous

Pumice

Pumice (Vesicular Felsic Igneous Rock)

Limonite or Ironstone (Hydrated iron oxide-hydroxide, approximately FeO(OH)·n(H2O)) — mineral

Limonite or Ironstone

Hydrated iron oxide-hydroxide, approximately FeO(OH)·n(H2O)

Fulgurite (Lechatelierite (Silica glass tubes)) — mineral

Fulgurite

Lechatelierite (Silica glass tubes)

Limonite (FeO(OH)·n(H2O)) — mineral

Limonite

FeO(OH)·n(H2O)

Limonite Nugget (Limonite (Hydrated iron oxide-hydroxide, FeO(OH)·nH2O)) — mineral

Limonite Nugget

Limonite (Hydrated iron oxide-hydroxide, FeO(OH)·nH2O)

Sandstone (Sedimentary Clastic Rock (Quartzose Sandstone)) — sedimentary

Sandstone

Sedimentary Clastic Rock (Quartzose Sandstone)

Pumice (Pumice (Volcanic glass / Felsic igneous rock)) — igneous

Pumice

Pumice (Volcanic glass / Felsic igneous rock)

Pebble (Lithified rock fragment / Sedimentary clast) — sedimentary

Pebble

Lithified rock fragment / Sedimentary clast

Limonite (FeO(OH)·nH2O) — mineral

Limonite

FeO(OH)·nH2O

Opalite (Synthetic Glass (Simulated Opal)) — gemstone

Opalite

Synthetic Glass (Simulated Opal)

Snowflake Obsidian (Volcanic Glass (SiO2 rich with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Volcanic Glass (SiO2 rich with Cristobalite inclusions)

Libyan Desert Glass (Libyan Desert Glass (Impactite)) — meteorite

Libyan Desert Glass

Libyan Desert Glass (Impactite)

Gossan (with Limonite and Hematite) (Goethite (FeO(OH)), Limonite (FeO(OH)·nH2O), and Hematite (Fe2O3)) — sedimentary

Gossan (with Limonite and Hematite)

Goethite (FeO(OH)), Limonite (FeO(OH)·nH2O), and Hematite (Fe2O3)

Tektite (specifically Indochinite) (Tektite (Natural silica glass)) — Mineraloid (Impact glass)

Tektite (specifically Indochinite)

Tektite (Natural silica glass)

Mineraloid (Impact glass)

Ironstone Concretion (Moqui Marble type) (Ferruginous Concretion (Fe2O3 / FeO(OH))) — sedimentary

Ironstone Concretion (Moqui Marble type)

Ferruginous Concretion (Fe2O3 / FeO(OH))

Ironstone with Pyrite (Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)) — sedimentary

Ironstone with Pyrite

Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)

Obsidian (Volcanic Glass (predominantly SiO2, approximately 70% or more)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2, approximately 70% or more)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Bauxite (Bauxite (Al2O3·2H2O)) — sedimentary

Bauxite

Bauxite (Al2O3·2H2O)

Snowflake Obsidian (Volcanic glass with Cristobalite inclusions (mostly SiO2)) — igneous

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Polished fossil-bearing amber cabochon (likely insect inclusion) (Fossilized plant resin; commonly Dominican or Baltic amber, chemically a complex diterpenoid resin) — fossil

Polished fossil-bearing amber cabochon (likely insect inclusion)

Fossilized plant resin; commonly Dominican or Baltic amber, chemically a complex diterpenoid resin

Obsidian (Volcanic Glass) — igneous

Obsidian

Volcanic Glass

Limonite with Gossan / Iron Ore (Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O) — mineral

Limonite with Gossan / Iron Ore

Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Limonite / Goethite Ironstone (FeO(OH)·nH2O (Hydrous iron oxide)) — mineral

Limonite / Goethite Ironstone

FeO(OH)·nH2O (Hydrous iron oxide)

Black Obsidian (Volcanic Glass (felsic volcanic glass, rich in SiO2)) — igneous

Black Obsidian

Volcanic Glass (felsic volcanic glass, rich in SiO2)

Polished amber (Amber (fossilized plant resin; chiefly polymerized diterpenoid resin)) — gemstone

Polished amber

Amber (fossilized plant resin; chiefly polymerized diterpenoid resin)

Red Coral (Sponge Coral / Apple Coral) (Corallium rubrum (calcium carbonate / organic gem)) — gemstone

Red Coral (Sponge Coral / Apple Coral)

Corallium rubrum (calcium carbonate / organic gem)

Sandstone (Clastic Sedimentary Rock) — sedimentary

Sandstone

Clastic Sedimentary Rock

Moldavite (Tektite (Natural Silicate Glass)) — gemstone

Moldavite

Tektite (Natural Silicate Glass)

Tektite (Natural Impact Glass) — meteorite

Tektite

Natural Impact Glass

Pumice (Volcanic glass / Pumice) — igneous

Pumice

Volcanic glass / Pumice