Chert (variations include Flint/Chalcedony)
Chert (SiO2 - Silicon Dioxide)
sedimentary
Category
Mineral (Or Mineraloid If Microcrystalline)
Browse mineral (or mineraloid if microcrystalline) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Red Jasper
Jasper (Silicon Dioxide) - SiO2
sedimentary/mineral
Red Jasper (River Polished)
Jasper (Silicon Dioxide, SiO2)
sedimentary/mineral
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
metamorphic
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Black Limestone with Calcite Veining
Bituminous Limestone (CaCO3 with Organic Carbon inclusions)
sedimentary
Jasper with Quartz Veining
Silicon Dioxide (SiO2) with impurities
sedimentary
Scoria (Volcanic Rock)
Scoria (often basaltic scoria)
Igneous
Precious Red Coral
Corallium rubrum / Corallium japonicum
mineral (organic gemstone)
Nephrite Jade
Tremolite-actinolite series (Ca2(Mg,Fe)5Si8O22(OH)2)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Green Jasper with Quartz veins
Jasper (Silicon Dioxide, SiO2)
sedimentary
River Pebbles (Sandstone and Quartzite)
SiO2 (Quartz) dominated clastic rocks
sedimentary and metamorphic
Banded Iron Formation
Banded Iron Formation (BIF)
Sedimentary
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Limestone with Chert or Siltstone bands
Sedimentary carbonate rock (CaCO3) often with siliceous impurities
sedimentary
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
metamorphic
Jasper (specifically Red Jasper)
Silicon Dioxide with Iron Oxides (SiO2 + Fe2O3)
sedimentary
Yellow Chert (Gold-colored River Pebble)
Microcrystalline Quartz (SiO2) with Limonite/Goethite staining
sedimentary
Basalt (with possible weathering or secondary mineral crust)
Basalt (Aphanitic Mafic Igneous Rock)
Igneous
Jasper and Quartz River Pebble
Silicon Dioxide (SiO2) with impurities
sedimentary
Wishing Stone (Basalt with Quartz Vein)
Basalt containing a microcrystalline quartz (SiO2) or calcite vein
igneous
Tiger's Eye and Carnelian Quartz
Silicon Dioxide (SiO2)
metamorphic and mineral
Jasper (specifically Brecciated or Agated Jasper)
Silicon Dioxide (SiO2) - Chalcedony with impurities
Mineral / Sedimentary
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Mineral (Organic Gemstone)
River Jasper (Green Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides (Goethite)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Jasper
Silicon Dioxide (SiO2) with iron and magnesium inclusions
sedimentary
Druzy Quartz on Chert/Siltstone
Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix
sedimentary
Brick
Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)
Man-made material (constructed)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Mineral/Fossil (Sedimentary context)
Red Jasper (Brecchiated Jasper)
Silicon Dioxide (SiO2) with Hematite impurities
Sedimentary / Mineral
Slate
Foliated Metamorphic Rock (primarily clay minerals and micas)
metamorphic
Green Moss Agate / Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron and Manganese inclusions
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Green Agate
Silicon dioxide (SiO₂)
mineral
Dyed Agate Slice
Silicon Dioxide (SiO2) with artificial colorants
Mineral (variety of Chalcedony)
Red Quartzite
Quartzite (SiO2)
metamorphic
Jasper (brecciated or orbicular variety)
Silicon dioxide (SiO2) with iron oxide inclusions
sedimentary/mineral