Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Category
Browse amorphous solid specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Granodiorite
Granodiorite (phaneritic intrusive igneous rock)
Quartzite (river pebble) and Gabbro (crushed rock)
Quartzite (metamorphosed Quartz Sandstone, SiO2) and Gabbro (Plagioclase-Clinopyroxene rock)
Pyrite (on Quartz/Host Rock)
Iron Sulfide (FeS₂)
Scoria
Vesicular Basalt / Scoriaceous Basalt
Scoria (Lava Rock)
Scoria (Vesicular Basaltic Rock)
Pumice (specifically a water-worn, weathered variety)
Vesicular volcanic glass
Porphyritic Andesite
Andesite (Porphyry)
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Host rock) with Quartz or Calcite amygdules
Jasper
Silicon dioxide (SiO2) with iron impurities
Basalt with Quartz/Calcite Vein
Basalt (Mafic Volcanic Rock with secondary mineralization)
Red Scoria (Lava Rock)
Scoria (Vesicular Basalt/Andesite)
Fossiliferous Chert (with Brachiopod or Mollusk fragments)
Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions
Satin Spar (commonly sold as Selenite)
Hydrous Calcium Sulfate (CaSO4·2H2O)
Howlite (Dyed to resemble Turquoise)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Sandstone (Quartzose Sandstone Pebble)
Arenite (primarily SiO2)
Basalt (River Rock pebble)
Basalt (a mafic extrusive igneous rock)
Pumice
Pumice (Highly vesicular volcanic glass)
Quartzite Cobble
Quartzite (composed primarily of SiO2)
Quartzite (Iron-stained)
Quartzite (primarily SiO2)
Basalt (Beach Pebble)
Basalt (Aphanitic Mafic Igneous Rock)
Andesite
Andesite
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Diabase (Greenstone)
Diabase or Dolerite
Quartz Pebble
Silicon dioxide (SiO2)
Sand Grain (Silica/Quartz Grain)
Silicon Dioxide (SiO2)
Green Aventurine (Fuchsite-bearing Quartz)
Silicon Dioxide with Chromium-rich Muscovite (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese
Silicon Carbide (Carborundum)
Silicon Carbide (SiC)
Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)
Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)
Rose Quartz
Silicon Dioxide (SiO2)
Banded Sandstone
Arenite with Liesegang banding
Diorite (Porphyritic)
Porphyritic Diorite
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Rose Quartz
Quartz (Silicon Dioxide, SiO2)
Gneiss (Granitic Gneiss)
Gneiss
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Pink Jade (Dyed Quartzite)
Silicon Dioxide (SiO2) - primarily Quartzite or Quartz
Red Howlite (Dyed)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5) with Red Dye
Yellow Quartz (Citrine Quartz)
Silicon Dioxide (SiO2)