Zinc Ore (Sphalerite in Matrix)
Sphalerite (Zn,Fe)S within a carbonate or silicate host rock
mineral
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Obsidian
Obsidian (Amorphous volcanic glass, SiO2 rich)
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Basalt
Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
igneous
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Chert (and Chalcedony/Agate mixture)
Microcrystalline Quartz (SiO2)
sedimentary
Granodiorite
Granodiorite (containing Quartz, Plagioclase Feldspar, Biotite, and Hornblende)
igneous
Quartzite with Hematite staining
Quartzite (SiO2) with iron oxide inclusions
metamorphic
Basalt with Iron Oxidation
Aphanitic Mafic Igneous Rock (composed primarily of Plagioclase and Pyroxene)
igneous
Sandstone (Quartzite-rich Cobble)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Milky Quartz
Quartz (SiO2)
mineral
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
mineral
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Slag (Industrial Glass Slag)
Amorphous Silica / Ferro-silicate Slag
mineraloid / anthropogenic
Dumortierite Quartz
Al7BO3(SiO4)3O3 (Aluminum borate silicate)
mineral
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Ironstone (with possible Hematite/Limonite coating)
Ironstone (Fe-rich sedimentary rock)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
mineral
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz with Hematite/Limonite oxides)
sedimentary
River Stone (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) based metamorphosed sandstone
metamorphic or sedimentary
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Quartz Druse (on Chalcedony/Agate base)
Silicon Dioxide (SiO2)
mineral
Blue Dyed Agate
Chalcedony (cryptocrystalline variety of Quartz), SiO2
mineral
Epidote
Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
mineral
Sunkissed Quartz or Hematoid Quartz
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
mineral
Chalcedony Nodule (Agate/Chert)
Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)
mineral
Jasper with Iron Staining
Silicon Dioxide (SiO2) with impurities
sedimentary
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Mineral
Basalt
Basalt (Extrusive Mafic Igneous)
igneous
Carnelian Agate Nodule
Silicon Dioxide (SiO2) - Carnelian Chalcedony
mineral
Aragonite / Calcite Geode
Calcium Carbonate (CaCO3)
mineral
Red Jasper
Jasper (Silicate mineral - SiO2)
sedimentary
Quartz
Silicon dioxide (SiO2)
Mineral
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Metamorphic (low-grade)
Lapis Lazuli
Lapis Lazuli (a rock composed primarily of Lazurite, Sodalite, Calcite, and Pyrite)
Mineral
Quartzite
Quartzite (Primary mineral: SiO2)
Metamorphic
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Mineral
Pink Dyed Agate (Pink Agate Slice)
Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz
mineral
Quartzite
Quartzite (Primary mineral: SiO2)
metamorphic
Nephrite Jade
Nephrite
Mineral/Rock
Galena
Lead(II) sulfide (PbS)
mineral