Gneiss Pebble
Gneiss
Category
Browse mineral, often found as detrital grains in sedimentary rocks specimens identified by the Rock Identifier community.
Gneiss Pebble
Gneiss
Turquoise (beads)
Turquoise; CuAl6(PO4)4(OH)8·4H2O
Marble
Recrystallized Calcite (CaCO3)
Ruby in Zoisite
Anyolite (Ruby in Zoisite)
Pyrite in Matrix (often with Chalcopyrite)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
Biotite (Black Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
Gneiss
Gneiss
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Ironstone Concretion (likely)
Goethite/Hematite/Limonite cemented sediment
Pink Quartzite
Quartzite (primarily SiO2 with iron oxide impurities)
Quartzite
Quartzite (composed primarily of SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Limonite
Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O
Quartzite
Quartzite (SiO2)
Gneiss
Gneiss
Sandstone (likely Siltstone or Mudstone variety)
Clastic Sedimentary Rock (primarily SiO2 with iron oxides)
Orange Calcite
Calcium Carbonate (CaCO3)
Chert Pebble (Jasper variant)
Microcrystalline Quartz (SiO2)
Limonite (Ironstone)
Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Chalcedony (Blue/Grey Lace Agate)
Silicon Dioxide (SiO2)
Quartzite Pebble (with Iron Staining)
Quartzite (SiO2)
Chert (and Quartz Gravel)
Chert (Cryptocrystalline Quartz, SiO2)
Quartzite
Quartzite (primarily SiO2)
Green Common Opal
Hydrated Silica (SiO2·nH2O)
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Quartzite river stone)
Microcrystalline Silicon Dioxide (SiO2)
Quartz (Sea Glass or River-worn Pebble style)
Silicon Dioxide (SiO2)
Pyrite with Iron Oxides (Fool's Gold in Matrix)
Iron Sulfide (FeS2)
Granite
Granite (a common igneous rock)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
Peridot (Olivine)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Kyanite
Kyanite (Al2SiO5)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Chalcedony Nodule (Agate/Chert)
Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Brecciated Chert
Sedimentary Chert (SiO2) with Calc-Silicate mineralization
Milky Quartz
Silicon Dioxide (SiO2)
Schist
Lepidoblastic Mica Schist