Carborundum (Silicon Carbide)
Silicon Carbide (SiC) / Moissanite (natural form)
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Carborundum (Silicon Carbide)
Silicon Carbide (SiC) / Moissanite (natural form)
Granite
Phaneritic Plutonic Rock (primarily SiO2, Al2O3, K2O, Na2O)
Gold Nugget
Native Gold (Au)
Slag (Industrial Glass)
Anthropogenic Vitreous Slag (Post-industrial byproduct)
Limonite (Iron Ore)
Limonite (Hydrous iron(III) oxide-hydroxide mixture, FeO(OH)·nH2O)
Limonite (Yellow Ochre)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 primary composition)
Pink Granite
Granite (Phaneritic Felsic Igneous Rock)
Jasper-Agate Breccia
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartz Pebble (Sea Glass-like Quartz)
Quartz (Silicon Dioxide - SiO2)
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Ferruginous Quartz (Agatized/Iron-stained Quartzite)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Chert (Arrowhead Artifact)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal Fragments)
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Green Aventurine
Silicon Dioxide (Quartz) with inclusions of Fuchsite mica; Chemical formula: SiO2 + K(Al,Cr)2AlSi3O10(OH)2
Bornite
Bornite (Cu5FeS4)
Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3(OH)4)
Onyx (Black Onyx)
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Graphite
Graphite (Native Carbon, C)
Chert / Flint Nodules
Cryptocrystalline Quartz (SiO2)
Mahogany Obsidian
Obsidian (volcanic glass with Hematite/Magnetite inclusions)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Snowflake Obsidian (Polished Cabochon)
Obsidian with Spherulitic Cristobalite (SiO2)
Ferruginous Quartz (Red Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Black Onyx
Silicon dioxide (SiO2) - Chalcedony variety
Amethyst Geode (Carved)
Amethyst (Violet Crystalline Quartz - SiO2)
Citrine Quartz
Crystalline Silicon Dioxide (SiO2) with Ferric Iron impurities
Apache Tear (Obsidian)
Obsidian (Hydrated Amorphous Silica, SiO2 + MgO/Fe3O4)
Sandstone
Arenite (SiO2 based with quartz, feldspar, or lithic fragments)
Coquina
Biogenic Limestone (Coquina)
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclastic Inclusions
Ironstone Concretion / Limonite-stained Siltstone
Ironstone (primarily Limonite FeO(OH)·nH2O and Siltstone)
Black Onyx
Silicon Dioxide (SiO2) - Chalcedony variant
Granite
Granite (Felsic Plutonic Rock)
Dalmatian Stone (Dalmation Jasper)
Aplite with Arfvedsonite inclusions
Carnelian Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Scoria (Lava Rock)
Scoria (Extrusive Igneous Rock)
Diamond
C (Native Carbon)