Gneiss
Gneiss (Metamorphic rock)
Category
Browse mineral, possibly rock fragment containing a mineral specimens identified by the Rock Identifier community.
Gneiss
Gneiss (Metamorphic rock)
Hag Stone
Perforated Chert (Microcrystalline Silica, SiO2)
Eudialyte
Eudialyte (Na4(Ca,Ce)2(Fe2+,Mn,Y)ZrSi8O22(OH,Cl)2)
Coquina / Fossiliferous Limestone
Calcite-rich Bioclastic Sedimentary Rock (CaCO3)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe/Chlorite)
Blue Quartz
Quartz (Silicon Dioxide) with blue inclusions (SiO2)
Green Moss Agate
Agate (Silicon Dioxide, SiO2) with inclusions of hornblende or chlorite
Granite
Granite (a felsic intrusive igneous rock composed primarily of quartz, feldspar, and mica)
Amber and Citrine Quartz
Succinite (Amber) and Silicon Dioxide (SiO2 / Citrine)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Amber
Succinite (approximate formula C10H16O)
Pyrite with Iron Oxides (Fool's Gold in Matrix)
Iron Sulfide (FeS2)
Amber
Succinite (C10H16O)
Amber
Succinite (fossilized resin, C10H16O)
Puddingstone
Conglomerate
Rhyolitic Tuff (Breccia Type)
Rhyolitic Pyroclastic Rock (Mixed Silicates including Quartz, Feldspar, and Volcanic Glass)
Quartz (Clear/White)
Silicon Dioxide (SiO2)
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Pyrite in Matrix (often with Chalcopyrite)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Fossilized Angel Wing Shell
Cyrtopleura costata
Orthoclase Feldspar
Orthoclase (KAlSi₃O₈)
Granite
Granite (Phaneritic Quartz-Feldspar Plutonic Rock)
Ironstone Concretion (Limonite/Goethite)
Ironstone (primarily FeO(OH)·nH2O)
Mahogany Obsidian
Volcanic glass containing Magnetite/Hematite
Diamond in Kimberlite
Kimberlite Matrix with Carbon (Diamond)
Foliated Metamorphic Rock (likely Gneiss or Schist)
Gneissic Metamorphic Rock
N/A (Non-Geological Specimen)
Mixed Tumbled Gemstones and River Rocks
Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)
Quartz (milky quartz variety)
Quartz (SiO₂)
Pietersite
Brecciated Chatoyant Tiger's Eye (SiO2)
Jasper Breccia
Silicon Dioxide (SiO2) - Brecciated Microcrystalline Quartz
Serpentine
Antigorite / Lizardite / Chrysotile [(Mg,Fe)3Si2O5(OH)4]
Serpentinite
Serpentinite (composed mainly of Group: Serpentine; (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Basalt
Basalt (a mafic extrusive igneous rock)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Chert (often found as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Shungite
Carbonaceous rock (primarily amorphous carbon)
Obsidian
Obsidian (Volcanic Glass)
Amber
Succinicum (C10H16O)