Rock Identifier

Category

Mineraloid (Impact Glass)

Browse mineraloid (impact glass) specimens identified by the Rock Identifier community.

Fulgurite (Fulgurite (Lechatelierite-rich fused silica)) — mineraloid / sedimentary (secondary formation)

Fulgurite

Fulgurite (Lechatelierite-rich fused silica)

mineraloid / sedimentary (secondary formation)

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

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Glass (Amorphous Silicon Dioxide (SiO2)) — mineraloid

Glass

Amorphous Silicon Dioxide (SiO2)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)

Snowflake Obsidian (Volcanic Glass with Cristobalite inclusions (70–75% SiO2)) — Igneous

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions (70–75% SiO2)

Mahogany Obsidian (Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)

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

Snowflake Obsidian

Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions

Black Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — igneous

Black Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Snowflake Obsidian (Volcanic Glass with Spherulite Inclusions (70-75% SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (70-75% SiO2)

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Mahogany Obsidian (Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2) — igneous

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2

Obsidian (Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)

Mahogany Obsidian (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass (SiO2 + Fe2O3)

Black Obsidian (Volcanic Glass (SiO2 + impurities)) — Igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities)

Sea Glass (Frosted Quartz/Glass) (Amorphous Silicon Dioxide (SiO2)) — Mineraloid

Sea Glass (Frosted Quartz/Glass)

Amorphous Silicon Dioxide (SiO2)

Obsidian (Gold Sheen) (Obsidian (SiO2 + impurities)) — igneous

Obsidian (Gold Sheen)

Obsidian (SiO2 + impurities)

Fulgurite (Fulgurite (Lechatelierite)) — metamorphic

Fulgurite

Fulgurite (Lechatelierite)

Cullet Glass (Slag Glass) (Amorphous Silicon Dioxide (Industrial Byproduct)) — mineraloid

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (Industrial Byproduct)

Cullet Glass (Man-made Glass Slag) (Amorphous Silica (SiO2) with chemical additives) — Mineraloid

Cullet Glass (Man-made Glass Slag)

Amorphous Silica (SiO2) with chemical additives

Mahogany Obsidian (Volcanic Glass (Silicate: SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass (Silicate: SiO2 + Fe2O3)

Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

Cullet (Slag Glass) (Amorphous Silica (Industrial byproduct)) — mineraloid

Cullet (Slag Glass)

Amorphous Silica (Industrial byproduct)

Cobalt Glass Slug (Man-made Glass) (Amorphous Silica with Cobalt Oxide (SiO2 + CoO)) — mineraloid

Cobalt Glass Slug (Man-made Glass)

Amorphous Silica with Cobalt Oxide (SiO2 + CoO)

Smoky Quartz with Iron Inclusions (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Obsidian (Obsidian (volcanic glass; primarily SiO2)) — igneous

Obsidian

Obsidian (volcanic glass; primarily SiO2)

Quartz Pebble (Sea Glass-like texture) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (Sea Glass-like texture)

Silicon Dioxide (SiO2)

Snowflake Obsidian (Volcanic glass containing Spherulites (SiO2)) — igneous

Snowflake Obsidian

Volcanic glass containing Spherulites (SiO2)

Snowflake Obsidian (Spherulitic Volcanic Glass (SiO2 + impurities)) — igneous

Snowflake Obsidian

Spherulitic Volcanic Glass (SiO2 + impurities)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Pumice (Vesicular Rhyolite / Pumice) — igneous

Pumice

Vesicular Rhyolite / Pumice

Cobalt Blue Slag Glass (Amorphous Silicon Dioxide (anthropogenic) with Cobalt additives) — mineraloid

Cobalt Blue Slag Glass

Amorphous Silicon Dioxide (anthropogenic) with Cobalt additives

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Obsidian (Volcanic Glass (Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic Glass (Silicon Dioxide with impurities)

Obsidian (Obsidian (Amorphous volcanic glass, SiO2 with impurities)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass, SiO2 with impurities)

Obsidian with Mahogany Phasing (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Obsidian with Mahogany Phasing

Volcanic Glass (SiO2 + Fe2O3)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Gold Sheen Obsidian (Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)) — igneous

Gold Sheen Obsidian

Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)

Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — Igneous

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Quartz (Sea Glass or River-worn Pebble style) (Silicon Dioxide (SiO2)) — mineral

Quartz (Sea Glass or River-worn Pebble style)

Silicon Dioxide (SiO2)