Chert / Flint
Cryptocrystalline Quartz (SiO2)
sedimentary
Category
Organic Structure (Not A Rock)
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Chert (Tan/Buff Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
mineral
Banded Sandstone
Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)
sedimentary
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Chert (White Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Green variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (Microcrystalline Quartz), SiO2
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chalcedony in Limestone Host Rock
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Mineral within Sedimentary Rock
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
mineral
Jasper with Quartz Vein
Silicon Dioxide (SiO2) with impurities
sedimentary
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Chert (Flint)
Chert (Cryptocrystalline Quartz, SiO2)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Chert (specifically Jasper or Flint variant)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Smooth River Pebble)
Silicon Dioxide (SiO2)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Green Sandstone
Glauconitic Sandstone
sedimentary
Chert (variant Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
mineral
Chert (specifically Yellow Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Vesicular Basalt with Quartz/Chalcedony
Vesicular Basalt (primarily Plagioclase, Pyroxene, and Olivine with SiO2 infill)
igneous
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Pearl
Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)
mineral
Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)
Porphyritic Basalt (Mafic Extrusive)
igneous
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
sedimentary
Chert (specifically Jasper or Flint type)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Gravel specimen)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically Chalcedony or Flint variation)
Microcrystalline Quartz (SiO2)
sedimentary
Amber / Copal
Succinite (fossilized resin)
mineraloid
Fossilized Sand Tiger Shark Tooth
Carcharias taurus / Striatolamia macrota (mineralized as Hydroxylapatite/Francolite)
sedimentary (fossil)