Mahogany Obsidian
Volcanic glass (SiO2 with Hematite or Magnetite inclusions)
igneous
Category
Mineraloid (Human Made Geological Specimen)
Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.
Chalcopyrite in Quartz (Gossan/Iron Hat)
CuFeS2 (Chalcopyrite) with SiO2 (Quartz)
mineral
Cobalt Blue Sea Glass
Amorphous Silica Glass (SiO2 + CoO)
mineraloid / anthropogenic material
Limonite
Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O
mineral
Chert (specifically Yellow/Brown Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Limonite/Goethite Nodule
Iron Oxyhydroxide (primarily FeO(OH)·nH2O)
mineral
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Sedimentary
Chert (and Jasper blend)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Fossiliferous Limestone with Rugose Coral
Calcite (CaCO3) containing a Rugosa (Horn Coral) fossil
sedimentary
Jasper Conglomerate
Jasperoid Conglomerate (predominantly SiO2 with iron oxide impurities)
sedimentary
Sandstone (with differential weathering)
Arenite / Quartz Sandstone (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Sandstone with Liesegang Rings
Arenite with Iron Oxide Concretions
sedimentary
Chert (specifically Yellow Jasper)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)
Mineral
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
sedimentary
Amethyst Geode
Silicon Dioxide with trace inclusions of Iron (SiO2)
mineral
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Kambaba Jasper (Crocodile Jasper)
Stromatolite (Fossilized Algae within Microcrystalline Quartz), SiO2
sedimentary
Eclogite
Eclogite (Omphacite + Pyrope)
metamorphic
Desert Rose
Gypsum (CaSO4·2H2O) or Barite (BaSO4) inclusions in sand
mineral
Quartz Geode with Calcite
Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)
Mineral/Geode
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Green Onyx (Banded Calcite)
Banded Calcite / Aragonite (CaCO3)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
River Rock (likely Quartzite or Chert)
Quartzite (primarily SiO2)
metamorphic
Chert
Chert (microcrystalline quartz, SiO2)
Sedimentary
Chert / Flint
Cryptocrystalline Quartz (SiO2)
sedimentary
Jasper in Rhyolite matrix
Silicon Dioxide (SiO2) with various inclusions in Felsic Igneous matrix
igneous
Mahogany Obsidian
Volcanic Glass (SiO2 + Fe2O3)
igneous
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Diamond
Native Carbon (C)
mineral
N/A (The provided image is a storyboard/digital document)
N/A
Chert (variations include Chalcedony and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Pink Jasper)
Microcrystalline Quartz (SiO2)
sedimentary