Chert (Flint Nodule)
Silicon Dioxide (SiO2)
Category
Browse sedimentary (if natural jasper) or artificial (if slag) specimens identified by the Rock Identifier community.
Chert (Flint Nodule)
Silicon Dioxide (SiO2)
Smoky Quartz (Chlorite Inclusions)
Silicon Dioxide (SiO2) with trace Aluminum and Natural Irradiation
Weathered reddish-brown rock fragment
Probably altered basalt or fine-grained volcanic rock; exact identification requires testing
Tumbled amber-colored chalcedony or jasper
Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper
Riverstone Jasper
Silicon Dioxide (SiO2) with impurities
Tumbled brecciated jasper
Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions
Chert (and Jasper) Nodules in Limestone
Silicon Dioxide (SiO2) microcrystalline quartz
Blue Agate (Tumbled and Dyed)
Silicon Dioxide (SiO2) with likely organic dyes
Jasper pebble (possibly Red Jasper or Lake Superior Agate/Jasper mix)
Silicon Dioxide (SiO2) with Hematite inclusions
Red Jasper Pebble
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Red Jasper (with Quartz and Chert)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Dyed Agate
Microcrystalline Quartz (SiO2) with artificial pigment
Jasper
Jasper (SiO2 plus impurities)
Red Jasper with Quartz Veining
Jasper (Silicon Dioxide, SiO2)
Red Jasper (Siltstone or Chert-based Jasper)
Silicon dioxide with hematite (SiO2 + Fe2O3)
Banded Ironstone / Jasper Siltstone
Siltstone with Iron Oxide Hydrates (SiO2 with Fe2O3/FeO(OH))
Jasper
Silicon dioxide / Chalcedony (SiO2)
Bismuth
Bismuth (Bi)
Tumbled brown quartz/chert pebble
Microcrystalline quartz (SiO₂), possibly chert or jasper
Banded Agate / Jasper (Chert Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Dyed Blue Agate
Cryptocrystalline Quartz (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide inclusions)
Dyed Agate
Agate (Cryptocrystalline Quartz), SiO2
Jasper pebble
Silicon Dioxide (SiO2 with iron oxide inclusions)
Jasper (Chert)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (Industrial Byproduct)
Red Jasper with Quartz
Silicon Dioxide (SiO2) with Hematite impurities
Jasper
Silicon Dioxide (SiO2) with impurities
Jasper with Hematite
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Heat-Treated Citrine (Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Chert with Chalcedony/Quartz Vug
Cryptocrystalline Silica (SiO2)
Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Blue Dyed Agate
Silicon Dioxide (SiO2) with artificial pigment
Polished tiger iron
Tiger iron; interlayered hematite, jasper, and crocidolite-quartz (often riebeckite)
Tumbled blue-green stone, likely chrysocolla or dyed chalcedony
Probable chrysocolla (hydrated copper aluminosilicate; variable composition), though appearance could also represent dyed chalcedony
Metallic sulfide mineral fragment, likely bornite or chalcopyrite
Bornite (Cu₅FeS₄) or chalcopyrite (CuFeS₂)
Jasper Pebble
Microcrystalline Quartz (SiO2)
Beach Pebbles and Jasper
Quartz / Microcrystalline Silicon Dioxide (SiO2)
Chalcopyrite (Peacock Ore)
Copper Iron Sulfide (CuFeS2)
Tumbled brown chalcedony (possibly carnelian or jasper)
Microcrystalline quartz, SiO₂; likely iron-stained chalcedony
Red jasper (likely polished/tumbled)
Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides