Rock Identifier

Category

Tektite (Natural Glass)

Browse tektite (natural glass) specimens identified by the Rock Identifier community.

Learn about Tektite (Natural Glass) in the encyclopedia

Macusanite

Moldavite

Obsidian

Black Obsidian

Green Obsidian

Blue Obsidian

Midnight Obsidian

Maskelynite

Pink Obsidian

Purple Obsidian

Purple Obsidian

Teal Obsidian

Yellow-Green Obsidian

Yellow-Green Obsidian

Quartzite (Quartzite (predominantly SiO2)) — metamorphic

Quartzite

Quartzite (predominantly SiO2)

Chert (specifically Dark Chert or Flint) (Silicon dioxide (SiO2)) — sedimentary

Chert (specifically Dark Chert or Flint)

Silicon dioxide (SiO2)

Chert (specifically Silex or Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Silex or Flint)

Microcrystalline Quartz (SiO2)

Tumbled blue-gray stone, likely quartzite or fine-grained basalt (Provisional identification: quartzite (mostly quartz, SiO₂) or basalt (plagioclase–pyroxene); image alone cannot distinguish reliably) — igneous

Tumbled blue-gray stone, likely quartzite or fine-grained basalt

Provisional identification: quartzite (mostly quartz, SiO₂) or basalt (plagioclase–pyroxene); image alone cannot distinguish reliably

Tumbled milky quartz (Quartz (silicon dioxide, SiO₂)) — mineral

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Amethyst (Silicon Dioxide (SiO2)) — mineral

Amethyst

Silicon Dioxide (SiO2)

Sandstone (likely Ferruginous) (Arenite (SiO2 based with Fe2O3/FeO(OH) cement)) — sedimentary

Sandstone (likely Ferruginous)

Arenite (SiO2 based with Fe2O3/FeO(OH) cement)

Celestine (Celestite) (Strontium sulfate (SrSO4)) — mineral

Celestine (Celestite)

Strontium sulfate (SrSO4)

Red cabochon gemstone, likely carnelian or dyed chalcedony (Chalcedony (microcrystalline quartz), SiO₂; exact identification requires testing) — gemstone

Red cabochon gemstone, likely carnelian or dyed chalcedony

Chalcedony (microcrystalline quartz), SiO₂; exact identification requires testing

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Pumice (Pumice (Vesicular volcanic glass)) — igneous

Pumice

Pumice (Vesicular volcanic glass)

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

Weathered Sandstone

Quartz Arenite / Clastic Sedimentary Rock

Amethyst (Quartz (Silicon Dioxide, SiO2)) — gemstone

Amethyst

Quartz (Silicon Dioxide, SiO2)

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

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Pumice (Pumice (Amorphous volcanic glass)) — igneous

Pumice

Pumice (Amorphous volcanic glass)

Pumice (Pumicite (Amorphous Volcanic Glass)) — igneous

Pumice

Pumicite (Amorphous Volcanic Glass)

Amethyst (Amethyst (Silicon Dioxide - SiO2 with iron impurities)) — mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

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

Smoky Quartz

Quartz (Silicon Dioxide, SiO2)

Amethyst (SiO2 (Silicon Dioxide with Iron impurities)) — mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Fulgurite (Lechatelierite (vitreous silica / silica glass)) — mineral

Fulgurite

Lechatelierite (vitreous silica / silica glass)

Sandstone (Weathered) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Weathered)

Arenite (primarily SiO2)

Red Sandstone (Arenite (SiO2 with Iron Oxide impurities)) — sedimentary

Red Sandstone

Arenite (SiO2 with Iron Oxide impurities)

Onyx (Black Onyx) (Onyx (Silicon Dioxide, SiO2)) — mineral

Onyx (Black Onyx)

Onyx (Silicon Dioxide, SiO2)

Milky and Citrine-type Quartz (Silicon Dioxide (SiO2)) — mineral

Milky and Citrine-type Quartz

Silicon Dioxide (SiO2)

Ruby (varieties of Corundum) (Aluminum oxide (Al2O3) with Chromium traces) — mineral

Ruby (varieties of Corundum)

Aluminum oxide (Al2O3) with Chromium traces

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartz (Citrine / Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine / Milky Quartz)

Silicon Dioxide (SiO2)

Golden Quartz (Citrine or Iron-stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Golden Quartz (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Synthetic Sapphire and Ion-X Glass (Single-crystal Alumina (Al2O3) and Ion-strengthened Aluminosilicate Glass) — mineral

Synthetic Sapphire and Ion-X Glass

Single-crystal Alumina (Al2O3) and Ion-strengthened Aluminosilicate Glass

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartz (Citrine appearance) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine appearance)

Silicon Dioxide (SiO2)

Green Onyx (Chalcedony (Silicon Dioxide, SiO2)) — gemstone

Green Onyx

Chalcedony (Silicon Dioxide, SiO2)

Smoky Quartz (SiO2 (Silicon Dioxide with aluminum impurities)) — mineral

Smoky Quartz

SiO2 (Silicon Dioxide with aluminum impurities)

Quartzite Pebble (Quartzite (SiO2-rich metamorphic rock)) — metamorphic

Quartzite Pebble

Quartzite (SiO2-rich metamorphic rock)

Sandstone Pebble (Arenite (SiO2 with various cementing agents)) — sedimentary

Sandstone Pebble

Arenite (SiO2 with various cementing agents)

Quartz-rich granite or granitic pegmatite (Coarse crystalline aggregate of quartz (SiO₂), feldspar, and mica; exact identification is uncertain from the image) — igneous

Quartz-rich granite or granitic pegmatite

Coarse crystalline aggregate of quartz (SiO₂), feldspar, and mica; exact identification is uncertain from the image

Tumbled milky quartz (Quartz, silicon dioxide (SiO₂)) — mineral

Tumbled milky quartz

Quartz, silicon dioxide (SiO₂)

Corundum (Sapphire / Raw Sapphire) (Aluminum Oxide (Al2O3)) — gemstone

Corundum (Sapphire / Raw Sapphire)

Aluminum Oxide (Al2O3)

Sandstone (Clastic sedimentary rock (primarily quartz arenite)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily quartz arenite)

Colorless faceted gemstone, likely cubic zirconia (Synthetic cubic zirconia (zirconium dioxide, ZrO₂); identity is visual and not definitive) — gemstone

Colorless faceted gemstone, likely cubic zirconia

Synthetic cubic zirconia (zirconium dioxide, ZrO₂); identity is visual and not definitive