Rock Identifier

Category

Glass

Browse glass specimens identified by the Rock Identifier community.

Learn about Glass in the encyclopedia

Sideromelane

Black Obsidian

Maskelynite

Obsidian

Tachylite

Hyalite Opal

Perlite

Opalite

Macusanite

Pink Obsidian

Goldstone

Palagonite

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Chert / Flint

Silicon Dioxide (SiO2)

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

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Fulgurite (Fulgurite (Lechatelierite or fused sand/quartz)) — mineral

Fulgurite

Fulgurite (Lechatelierite or fused sand/quartz)

Snowflake obsidian cabochon (Obsidian (volcanic glass), SiO₂-rich; white areas are cristobalite/spherulitic devitrification) — igneous

Snowflake obsidian cabochon

Obsidian (volcanic glass), SiO₂-rich; white areas are cristobalite/spherulitic devitrification

Opalite-style pendant (likely synthetic glass, not natural opal) (Opalescent glass; commonly sold as “opalite” (not a recognized mineral species)) — gemstone

Opalite-style pendant (likely synthetic glass, not natural opal)

Opalescent glass; commonly sold as “opalite” (not a recognized mineral species)

Likely polished dark stone or glassy mineral bead (Indeterminate; possibly obsidian, hematite, or a dark agate) — mineral

Likely polished dark stone or glassy mineral bead

Indeterminate; possibly obsidian, hematite, or a dark agate

Small tumbled quartz-like pebble (Likely quartz (SiO₂), possibly milky quartz or pale chalcedony) — mineral

Small tumbled quartz-like pebble

Likely quartz (SiO₂), possibly milky quartz or pale chalcedony

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

Chert (Fossiliferous Chert/Flint)

Silicon Dioxide (SiO2)

Glass / Silicon Dioxide (Man-made) (SiO2 (Amorphous Silicon Dioxide)) — Amorphous Solid

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)

Amorphous Solid

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

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Obsidian (Obsidian (principally SiO2 - Silicon Dioxide)) — igneous

Obsidian

Obsidian (principally SiO2 - Silicon Dioxide)

Opalite Egg (Synthetic Glass (Simulated Opal)) — mineral

Opalite Egg

Synthetic Glass (Simulated Opal)

Prasiolite (Green Quartz) / Sea Glass Amalgam (SiO2 (Silicon Dioxide)) — mineral

Prasiolite (Green Quartz) / Sea Glass Amalgam

SiO2 (Silicon Dioxide)

Tumbled opalite (likely synthetic glass) (Opalite; typically man-made opalescent soda-lime glass, not a recognized mineral species) — gemstone

Tumbled opalite (likely synthetic glass)

Opalite; typically man-made opalescent soda-lime glass, not a recognized mineral species

Green glass sphere/marble (Soda-lime glass (primarily SiO2, Na2O, CaO)) — Man-made object (Simulant)

Green glass sphere/marble

Soda-lime glass (primarily SiO2, Na2O, CaO)

Man-made object (Simulant)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Sea Glass (Turquoise/Aqua) (Amorphous Silica (SiO2) with transition metal dopants) — Anthropogenic (Man-made material processed by nature)

Sea Glass (Turquoise/Aqua)

Amorphous Silica (SiO2) with transition metal dopants

Anthropogenic (Man-made material processed by nature)

Blue chalcedony cabochon (probable) (Chalcedony, a cryptocrystalline variety of quartz; silicon dioxide, SiO₂) — gemstone

Blue chalcedony cabochon (probable)

Chalcedony, a cryptocrystalline variety of quartz; silicon dioxide, SiO₂

Tumbled Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Tumbled Quartz Pebble

Silicon Dioxide (SiO2)

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

Chert (Flint Gravel)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Rock crystal (clear quartz), possibly cloudy quartz (Quartz, silicon dioxide (SiO₂)) — mineral

Rock crystal (clear quartz), possibly cloudy quartz

Quartz, silicon dioxide (SiO₂)

Snowflake Obsidian (Volcanic Glass (spherulitic obsidian)) — igneous

Snowflake Obsidian

Volcanic Glass (spherulitic obsidian)

Snowflake Obsidian (Volcanic Glass (felsic volcanic glass with cristobalite inclusions)) — igneous

Snowflake Obsidian

Volcanic Glass (felsic volcanic glass with cristobalite inclusions)

Green Aventurine (Quartz (Silicon Dioxide, SiO2) with fuchsite inclusions) — mineral

Green Aventurine

Quartz (Silicon Dioxide, SiO2) with fuchsite inclusions

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

Chert (Flint/Jasper)

Silicon Dioxide (SiO2)

Tumbled rose quartz (probable) (Quartz, silicon dioxide (SiO₂), pink variety) — mineral

Tumbled rose quartz (probable)

Quartz, silicon dioxide (SiO₂), pink variety

Sea Glass (Silica (SiO2) - Amorphous) — Mineral

Sea Glass

Silica (SiO2) - Amorphous

Sea Glass (Amorphous silicon dioxide (glass)) — mineral

Sea Glass

Amorphous silicon dioxide (glass)

Sea Glass (Man-made vitreous material (silica-based glass)) — mineral

Sea Glass

Man-made vitreous material (silica-based glass)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Red Quartz (Tumbled) (Silicon Dioxide with Iron Oxide inclusions (SiO2)) — mineral

Red Quartz (Tumbled)

Silicon Dioxide with Iron Oxide inclusions (SiO2)

Raw pale-green crystal, likely fluorite (Fluorite (calcium fluoride, CaF₂)) — mineral

Raw pale-green crystal, likely fluorite

Fluorite (calcium fluoride, CaF₂)

Clear quartz fragment (Quartz (silicon dioxide, SiO₂)) — mineral

Clear quartz fragment

Quartz (silicon dioxide, SiO₂)

White tumbled stone, likely quartz or calcite (Indeterminate; possibly quartz (SiO₂) or calcite (CaCO₃)) — mineral

White tumbled stone, likely quartz or calcite

Indeterminate; possibly quartz (SiO₂) or calcite (CaCO₃)

Milky quartz (likely rough quartz crystal) (Quartz, silicon dioxide (SiO₂)) — mineral

Milky quartz (likely rough quartz crystal)

Quartz, silicon dioxide (SiO₂)

Blue Goldstone (Aventurine Glass (SiO2 with Cobalt/Copper inclusions)) — man-made glass

Blue Goldstone

Aventurine Glass (SiO2 with Cobalt/Copper inclusions)

Muscovite Mica (KAl2(AlSi3O10)(F,OH)2) — mineral

Muscovite Mica

KAl2(AlSi3O10)(F,OH)2

Snowflake Obsidian (Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)