Obsidian / Volcanic Glass
Obsidian (principally SiO2, usually 70% or more)
Category
Browse not a rock (animated character) specimens identified by the Rock Identifier community.
Obsidian / Volcanic Glass
Obsidian (principally SiO2, usually 70% or more)
Rhodonite
Manganese silicate (Mn,Fe,Mg,Ca)SiO3
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Vesicular Basalt
Extrusive mafic igneous rock (primarily Plagioclase feldspar and Pyroxene)
Agate
Silicon Dioxide (SiO2) - Variety of Chalcedony
Bloodstone (Heliotrope)
Silicon Dioxide (SiO2) - Variety of Chalcedony/Jasper
Quartzite
Quartzite (primarily SiO2)
Bauxite / Iron-rich Laterite
Laterite (principally Al(OH)3, Fe2O3, and SiO2)
Red Jasper
Jasper (Silicon Dioxide) - SiO2
Blue Zircon
Zirconium Silicate (ZrSiO4)
Pyrite
Iron Sulfide (FeS2)
Citrine
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
Green Fluorite
Fluorite (Calcium Fluoride - CaF2)
Anthracite Coal
Low-grade metamorphic carbonaceous rock
Granite
Phaneritic intrusive felsic igneous rock
Diorite
Diorite (Intermediate intrusive igneous rock)
Anthracite Coal
Anthracite (Carbon-based sedimentary-metamorphic rock)
Sandstone
Quartz Arenite (a type of sandstone composed of more than 90% quartz)
Breccia
Breccia (Clastic Sedimentary Rock)
Quartz with Limonite Staining
Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)
Quartz Pebble
Silicon Dioxide (SiO2)
Fossilized Horn Coral
Order Rugosa (Rugose Coral)
Yellow Quartzite (River Pebble)
Quartzite (primarily SiO2)
Chert with Quartz/Calcite Vein
Microcrystalline Silica (SiO2)
Rock Salt / Halite Crust
Halite (Sodium Chloride, NaCl)
Bloodstone Jasper (Heliotrope)
SiO2 (Silicon Dioxide) - Cryptocrystalline Quartz
Jasper (specifically Brecciated or Agated Jasper)
Silicon Dioxide (SiO2) - Chalcedony with impurities
Green Jasper (Heliotrope / Bloodstone variety)
Silicon Dioxide (SiO₂)
Gneiss
Gneiss
Tufa
Calcareous Tufa (CaCO3)
Blue Goldstone
Synthetic Avanturine Glass (or Aventurine Glass)
Limestone
Calcium Carbonate (CaCO3)
Schist
Mica Schist (primarily consisting of muscovite KAl2(AlSi3O10)(OH)2 or biotite K(Mg,Fe)3(AlSi3O10)(OH)2)
Mica Schist
Crystalline Schist (often containing Muscovite, Biotite, and Quartz)
Coal (Anthracite)
Anthracite (Carbon-based organic sedimentary/metamorphic rock)
Oolitic Ironstone
Sedimentary Ooidal Ironstone (Limonite/Hematite mixture)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - variety Carnelian (Chalcedony)