Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
Category
Browse sedimentary (volcanic) specimens identified by the Rock Identifier community.
Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Hematite
Hematite (Fe2O3)
Carnelian
Carnelian (Silicon Dioxide - SiO2)
Carnelian
Carnelian (Silicon Dioxide: SiO2 with Iron Oxide impurities)
Jasper
Silicon Dioxide (SiO2) with impurities
Carnelian Agate
Silicon Dioxide (SiO2)
Agate / Banded Chalcedony
Agate (Silicon Dioxide / SiO2)
Geode (unopened nodule)
Silicon Dioxide (SiO2) Nodule
Chert (Common Opal/Chalcedony mixture)
Silicon Dioxide (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Amethyst (Geode/Druzy)
Silicon Dioxide (SiO2) with iron impurities
Opal
Hydrated amorphous form of silica (SiO2·nH2O)
Jasper
Silicon Dioxide (SiO2) with impurities
Jasper (Chert)
Silicon Dioxide (SiO2)
Common Opal
Hydrated amorphous form of silica (SiO2·nH2O)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Botryoidal Agate / Chalcedony Geode
Silicon Dioxide (SiO2)
Dalmatian Jasper
Dalmatian Stone (a microcrystalline quartz and feldspar rock with arfvedsonite)
Chalcedony
Silicon Dioxide (SiO2)
Ocean Jasper
Spherulitic Chalcedony (SiO2)
Native Gold
Native Gold (Au)
Zebra Jasper
Silicon Dioxide (SiO2) with various inclusions
Yellow Chalcedony (common opal or chert variant)
Silicon Dioxide (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)
Cryptocrystalline Quartz (SiO2) with inclusions
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Sulfur (with possible Cullet Glass or Slag imitation)
Native Sulfur (S8)
Quartz Geode with Goethite/Hematite
Silicon Dioxide (SiO2) with Iron Oxides
Red Jasper
Jasper (Silicate mineral - SiO2)
Carnelian Agate
Chalcedony (Silicon Dioxide, SiO2) with Iron Oxide impurities
Blue Chalcedony
Silicon Dioxide (SiO2)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Banded Chert (Agate)
Silicon Dioxide (SiO2)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Chalcedony (Botryoidal/Tumbled Agate)
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Carnelian
Chalcedony (SiO2)
Jasper
Silicon dioxide (SiO2)
Jasper with Quartz
Silicon Dioxide (SiO2) - Chalcedony variety