Pink Granite with Quartz Vein
Phaneritic Plutonic Felsic Rock (K-feldspar + Quartz + Plagioclase + Mica)
igneous
Category
Igneous Rock (Volcanic Glass)
Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.
Quartz (Iron-Stained Quartz Pebble)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
mineral
Tektite (Indochinite)
Tektite (High-silica natural glass)
igneous
Jasper (likely Lake Superior Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary (silica-rich mineral variety)
Blue Sapphire
Corundum (Al2O3)
mineral
Pink Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Plagioclase Feldspar
Plagioclase Feldspar Series (NaAlSi3O8 - CaAl2Si2O8)
Mineral
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Igneous
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Banded Agate (Pink Chalcedony)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Jasper (Red)
Silicon Dioxide (SiO2)
sedimentary
Biotite Mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
Mineral
Quartz (specifically Citrine or Yellow Quartzite pebble)
Silicon Dioxide (SiO2)
mineral
Ferrous Slag (Iron Smelting By-product)
Fused Siliceous Slag
Anthropogenic Material (Man-made Rock)
Obsidian
Obsidian (principally SiO2)
igneous
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Diorite
Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)
igneous
Obsidian (Apache Tear)
Obsidian (Amorphous Volcanic Glass / SiO2 with impurities)
igneous
Obsidian
Obsidian (volcanic glass), predominantly amorphous SiO₂
Igneous
Apache Tear
Obsidian (Hydrated Silica / Amorphous Volcanic Glass)
igneous
Obsidian
Obsidian (Volcanic glass), SiO2 (major component)
igneous
Apache Tear
Obsidian (Volcanic Glass), SiO2 + MgO, Fe3O4
igneous
Obsidian (Apache Tear)
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
igneous
Blue Moss Agate / Blue Chalcedony
Silicon Dioxide (SiO2)
mineral
Apache Tear (Obsidian)
Obsidian / Amorphous Volcanic Glass (primarily SiO2)
igneous
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
igneous
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Clear Quartz
Silicon Dioxide (SiO2) / Rock Crystal
mineral
Granite (weathered pebble)
Granite (plutonic igneous rock)
Igneous
Quartz (Milky and Bull Quartz)
Silicon Dioxide (SiO2)
mineral
Amygdaloidal Basalt with Quartz/Zeolite Infill
Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)
igneous
Porphyritic Basalt or Diabase with Plagioclase Phenocrysts
Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar
Igneous
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Quartzite (river pebble) and Gabbro (crushed rock)
Quartzite (metamorphosed Quartz Sandstone, SiO2) and Gabbro (Plagioclase-Clinopyroxene rock)
Metamorphic and Igneous
Quartz Vein with Iron Staining
Silicon Dioxide (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Epidosite (Epidote-rich rock)
Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
metamorphic
Feldspar (specifically Orthoclase)
Potassium Aluminum Silicate (KAlSi3O8)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral