Limonite (Ironstone Concretion)
Hydrous ferric oxides (FeO(OH)·nH2O)
Category
Browse igneous and metamorphic derivative (weathered) specimens identified by the Rock Identifier community.
Limonite (Ironstone Concretion)
Hydrous ferric oxides (FeO(OH)·nH2O)
Mookaite Jasper
Silicified Radiolarite (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert / Chalcedony
Silicon Dioxide (SiO2)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Limonite (vibrant yellowish-brown iron oxide)
Limonite (FeO(OH)·nH2O)
Limonite
Limonite (Hydrous iron oxides, FeO(OH)·nH2O)
Agate
Silicon dioxide (SiO2) - variety Chalcedony
Chert (Flint)
Cryptocrystalline Silica (SiO2)
Chert (Arrowhead variety)
Chert (SiO2)
Fire Opal (in matrix)
Hydrated Silica (SiO2·nH2O)
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite/Iron inclusions
Grey Chalcedony
Silicon Dioxide (SiO2)
Schist
Mica Schist
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Calcite (Yellow/Orange variety - sometimes called Honey Calcite)
Calcite
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Milky Quartz (Common Quartz)
Quartz (Silicon Dioxide, SiO2)
Basalt (Vesicular)
Basalt (Mafic Extrusive Igneous Rock)
Granodiorite
Granodiorite (containing Plagioclase, Quartz, and K-feldspar)
Basalt with Iron Oxidation
Extrusive Mafic Igneous Rock (composed of Plagioclase and Pyroxene)
Basalt (with possible iron oxide staining)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt
Mafic Extrusive Igneous Rock
Quartz Pebble
Silicon Dioxide (SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Banded Gneiss
Gneiss (pronounced 'nice')
Echinoid Fossil (Sea Urchin)
Echinoidea (specifically likely Schizaster or similar genus), calcium carbonate (CaCO3)
Trilobite Fossil (Flexicalymene)
Flexicalymene ouzregui
Gneiss
Foliated Metamorphic Rock
Aventurine
Silicon Dioxide (SiO2) with inclusions
Corundum (Sapphire/Ruby in Matrix)
Corundum (Al2O3)
Magnetite (Lodestone)
Magnetite (Fe3O4)
Muscovite
Muscovite (KAl2(AlSi3O10)(OH)2)
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
Muscovite Mica
Muscovite: KAl2(AlSi3O10)(OH)2
Greenstone / Greenschist
Chlorite schist / Epidiorite
Biotite Mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
Limonite with Hematite
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Hematite
Hematite (Fe2O3)