Obsidian Arrowhead
Obsidian (volcanic glass, SiO2 rich)
Category
Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.
Obsidian Arrowhead
Obsidian (volcanic glass, SiO2 rich)
Quartz Crystal
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Chert (often called Jasper or Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Auriferous Quartz (Gold-bearing Quartz)
Silicon Dioxide (SiO2) with trace Gold (Au) and Iron Oxides
Quartz Pebble
Silicon Dioxide (SiO2)
Granite
Phaneritic high-silica plutonic rock (composed primarily of Quartz, Feldspar, and Mica)
Quartzite
Quartzite (SiO2)
Diamond
Carbon (C)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Quartz
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide)
Quartzite
Metamorphic Quartzite (SiO2)
Fossilized Shark Tooth (Sand Tiger)
Carcharias taurus (fossil specimen)
Mahogany Obsidian
Obsidian (volcanic glass with hematite/magnetite inclusions)
Unakite (polished/tumbled)
Unakite, a hydrothermally altered granite composed mainly of epidote, pink potassium feldspar (orthoclase/microcline), and quartz
Quartz with Orthoclase Feldspar
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate (KAlSi3O8)
Basalt with Quartz Vein
Basaltic rock with hydrothermal SiO2 filling
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Basalt Pebble
Basalt (Mafic volcanic rock)
Petrified Wood
Silicified Wood (SiO2)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) in matrix
Yellow Jasper
Silicon dioxide (SiO2)
Garnet Schist
Almandine-Mica Schist
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Oyster (Devil's Toenail)
Gryphaea (extinct genus of bivalve mollusks)
Garnet Schist
Garnet-bearing Mica Schist (variety of compositions, often Al2SiO5 with X3Y2(SiO4)3)
Favosites Fossil (Honeycomb Coral)
Favosites sp. (Extinct genus of tabulate coral)
Petrified Wood
Silicified Wood (SiO2)
Porphyritic Rhyolite
Porphyritic Rhyolite (SiO2)
Banded Chert with Quartz Veining
Microcrystalline Quartz (SiO2)
Quartz
Silicon dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Quartz Mineral
Silicon Dioxide (SiO2)