Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Category
Browse igneous rock specimens identified by the Rock Identifier community.
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Granite
Granite (High-silica plutonic rock)
Diorite
Phaneritic Intermediate Plutonic Rock (Diorite)
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Diorite Gneiss
Foliated Diorite Gneiss
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Pumice
Pumice (Volcanic glass with vesicular texture)
Basalt with Quartz Vein and Weathering Crust
Amygdaloidal or Porphyritic Basalt
Pumice
Pumice (a volcanic glass, primarily SiO2 with Al2O3)
Pumice
Vesicular Rhyolite / Pumice
Wonderstone
Rhyolite (Silicon Dioxide with Iron Oxide impurities)
Pumice
Vesicular volcanic glass (Amorphous silica mixed with various oxides)
Granite (including Pegmatite variants)
Phaneritic Plutonic Rock (composed primarily of Quartz SiO2, Feldspar KAlSi3O8, and Biotite/Muscovite mica)
Basalt
Mafic volcanic rock (Silicon dioxide 45-52%)
Pumice
Pumice (a highly vesicular volcanic glass)
Vesicular Basalt with Amygdules
Amygdaloidal Basalt
Pumice
Vesicular Rhyolite or Dacite Pumice (Amorphous volcanic glass)
Thunderegg (Agetized Geode nodule)
Rhyolitic Agate Nodule (SiO2 filling volcanic cavities)
Granite
Phaneritic plutonic rock (SiO2 range 70-75%)
Quartz (Milk Quartz / Massive Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Gneiss (Metamorphic Rock)
Gneiss
Coarse Sand Grain / Lithic Fragment
Clastic Sediment (Lithic fragment or Quartz/Feldspar grain)
Quartz Geode
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Blue Sapphire
Corundum (Al2O3) with traces of Iron and Titanium
Quartz Geode
Silicon Dioxide (SiO2)
Diorite (River Pebble)
Phaneritic Intermediate Plutonic Rock (Diorite)
Basalt River Pebble
Basalt (Aphanitic Mafic Volcanic Rock)
Diorite
Phaneritic Intermediate Plutonic Rock (Diorite)
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
Granite Pebble
Granite (Phaneritic Quartz-Feldspar Rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Amygdaloidal Rhyolite
Amygdaloidal Rhyolite (Felsic volcanic rock)
Pumice
Pumice (a highly vesicular volcanic rock)
Porphyritic Rhyolite (Red Porphyry)
Porphyritic Rhyolite (Felsic volcanic rock)
Granite
Granite (Phaneritic Quartz-Feldspar Rock)
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)