Chert (Jasper/Chalcedony variety)
Silicon Dioxide (SiO2)
Category
Browse mineral (specifically a variety of chalcedony, which is a microcrystalline quartz) specimens identified by the Rock Identifier community.
Chert (Jasper/Chalcedony variety)
Silicon Dioxide (SiO2)
Obsidian (specifically Mahogany Obsidian)
Volcanic glass (high silica content, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (possibly milky quartz or quartz with inclusions)
SiO2 (Silicon Dioxide)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Black Onyx
Chalcedony (SiO2) with parallel banding
Fossil Shark Tooth (Otodus obliquus)
Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))
Quartz (Iron-stained or Milky Quartz)
Silicon Dioxide (SiO2)
Common Opal
Amorphous Hydrated Silica (SiO2·nH2O)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2)
Chert (specifically Flint or Nodular Chert)
Silicon Dioxide (SiO2)
Limestone (specifically Fossiliferous or Crinoidal Limestone)
Calcium Carbonate (CaCO3) - Calcite Rock
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Granite
Granite (Felsic Plutonic Rock)
Quartzite
Quartzite (primarily SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Leopard Skin Jasper
Jasper (Silicon Dioxide with impurities), SiO2
Green Aventurine
Silicon Dioxide (Quartz) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)
Chert (specifically Flint or Common Opal fragment)
Cryptocrystalline Silica (SiO2)
Bloodstone
Heliotrope (a variety of Cryptocrystalline Quartz / Jasper, SiO2)
Quartz (Smoky/Clear variety)
Silicon Dioxide (SiO2)
Raw Citrine (Yellow Quartz)
Citrine / Silicon Dioxide (SiO2)
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (specifically an Iron-Concretion)
Arenite with Iron Oxide (Limonite/Goethite) cementation
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite or Magnetite inclusions, SiO2 (Silicon Dioxide)
Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Blue Sapphire
Corundum (Al2O3 with trace amounts of iron and titanium)
Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (often called Jasper in this color)
Microcrystalline quartz (SiO2)