Geode (unopened)
Calcedony-lined Geode (SiO2)
sedimentary
Category
This Is Not A Rock Or Mineral
Browse this is not a rock or mineral specimens identified by the Rock Identifier community.
Granodiorite
Granodiorite (intermediate intrusive igneous rock)
igneous
Clay Brick
Ceramic structural unit (Al2O3·2SiO2·2H2O as precursor)
metamorphic (man-made/anthropogenic)
Basalt
Basalt
igneous
Gold Ore
Auriferous Quartz and Sulfide Mineralization in Host Rock
igneous
Ironstone Concretion (Boji Stone/Moqui Marble type)
Goethite/Hematite-encrusted Sandstone Concretion
sedimentary
Fluorite (likely Green Fluorite variant)
Calcium Fluoride (CaF2)
mineral
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock
igneous
Iolite-bearing Gneiss (Cordierite)
Cordierite (Mg2Al4Si5O18) in Gneiss matrix
metamorphic
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Sodalite Syenite
Sodalite-bearing Syenite (Na8(Al6Si6O24)Cl2)
igneous
Banded Chalcedony (Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Dyed Purple Agate
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
mineral
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Petoskey Stone (Petrified Favosites)
Favosites (extinct colonial coral), CaCO3 with Silica replacement
sedimentary
Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Jasper
Silicon dioxide (SiO2) with iron impurities
sedimentary
Carnelian
Carnelian (Silicon Dioxide - SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Carnelian
Carnelian (a variety of Chalcedony); SiO2 (Silicon Dioxide)
mineral
Druzy Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Agate (specifically Eye Agate / Chalcedony)
Agate (Cryptocrystalline variety of Quartz, SiO2)
mineral
Carnelian
Carnelian Chalcedony (SiO2 with Iron Oxide impurities)
mineral
Fossilized Crinoid Stem
Class Crinoidea (Echinodermata)
sedimentary
Carnelian (Agate)
SiO2 (Silicon Dioxide with Iron Oxide impurities)
mineral
Green Agate
Silicon Dioxide (SiO2) - Chalcedony variety
mineral
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Sandstone (Wonderstone)
Silicified Sandstone / Orthoquartzite with Liesegang rings
sedimentary
Lapis Lazuli
Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, along with Calcite and Pyrite)
metamorphic
Quartz (Milky/Yellowish variety)
Silicon Dioxide (SiO2)
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Granitoid (Granite/Gneiss)
Granitoid silicate rock, primarily quartz and feldspar
igneous/metamorphic
Basalt
Basalt (Aphanitic mafic volcanic rock)
igneous
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
sedimentary
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
sedimentary
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Pink Granite
Phaneritic Plutonic Igneous Rock (high K-feldspar)
igneous
Chert (White-Tan variety)
Silicon dioxide (SiO2) / Microcrystalline Quartz
sedimentary