Chalcedony (likely agate/chert fragment)
Microcrystalline quartz, SiO₂
Category
Browse mineral (or mineraloid if microcrystalline) specimens identified by the Rock Identifier community.
Chalcedony (likely agate/chert fragment)
Microcrystalline quartz, SiO₂
Chalcedony (gray-white agate)
Microcrystalline quartz, SiO₂
Jasper
Microcrystalline Quartz (SiO2)
Red Jasper Cube
SiO2 (microcrystalline quartz)
Yellow Jasper
SiO2 (Microcrystalline Quartz)
Banded Agate (Dyed / Polished)
Microcrystalline Quartz (SiO2)
Dendritic Jasper
SiO2 (Microcrystalline Quartz)
Chalcedony (Agate/Chert)
Microcrystalline Quartz (SiO2)
Chalcedony (Commonly known as Carnelian or Agate pebble)
Microcrystalline Quartz (SiO2)
Chalcedony (Botryoidal/Agate nodule)
Microcrystalline Quartz (SiO2)
Red Jasper
SiO2 (Microcrystalline Quartz)
Chalcedony (Yellow Jasper or Agate)
Microcrystalline Quartz (SiO2)
Black Chert
Chert (microcrystalline quartz)
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
Grey Chalcedony (Tumbled Moon)
Microcrystalline Quartz (SiO2)
Chalcedony Geode Fragment
Microcrystalline Quartz (SiO2)
Jasper (Mookaite variety likely)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Green Aventurine
Silicon dioxide (SiO2) with Fuchsite inclusions
Red Jasper (Opaque Chalcedony)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Limonite and Goethite Iron Ore
Hydrated Iron Oxide Hydroxide (FeO(OH)·nH2O)
Yellow Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Agate
SiO2 (Silicon dioxide, cryptocrystalline quartz)
Petrified Wood / Fossilized Wood
Silicified Wood (Silicon Dioxide - SiO2)
Dalmatian Jasper
Peralkaline Quartz-feldspathic Rock (Arfvedsonite-bearing)
Chalcedony (Agate / Quartz Beach Pebble)
Silicon Dioxide (SiO2)
Limonite on Sandstone
Iron Oxyhydroxide (FeO(OH)·nH2O) on Quartz Sandstone
Dalmatian Jasper
Dalmatian Stone (Arfvedsonite/Albite Microquartz)
Greenstone / Serpentinite
Serpentine-group / Altered Mafic Rock
Geode / Fossilized Gastropod or Shell Cast
Silicon dioxide (Quartz) replacement / fossil mold
Yellow Ochre (Limonite)
Limonite (FeO(OH)qnH2O)
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Chert (Septarian Concretion/Nodule)
Microcrystalline silica (SiO2) with carbonate mineral veining
Aventurine (Tan/Cream colored)
Quartz (SiO2) with mineral inclusions
Polished Agate (Yellow/Grey Agate Pendant)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz / Chalcedony replacement)
Petrified Wood
Silicified wood (primarily quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (Quartz / Chalcedony replacement of organic cellulose)
Limonite
Limonite (FeOO·nH2O)
Bauxite
Aluminium ore (Hydrated aluminium oxides AlOx(OH)3-2x)
Jasper
Microcrystalline Quartz (SiO2)