Likely weathered chert or siliceous shale
Cryptocrystalline quartz (SiO₂), possibly with clay minerals
Category
Browse mineral or sedimentary (if chert) specimens identified by the Rock Identifier community.
Likely weathered chert or siliceous shale
Cryptocrystalline quartz (SiO₂), possibly with clay minerals
Chert (likely jasper-bearing chert)
Microcrystalline quartz (SiO₂), with iron-oxide staining and possible chalcedony
Banded Chert / Chalcedony
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Chert (with Lichen)
Microcrystalline Quartz (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (Serpentinized)
Silicon Dioxide (SiO2) with mineral staining
Likely polished dark stone (identity uncertain)
Undetermined; possibly polished basalt, chert, or another dark silicate rock
Chert (Jasper or Flint variant)
Chert (composed of microcrystalline quartz, SiO2)
Chert
Chert (Microcrystalline Quartz)
Likely flint or chert fragment
Microcrystalline quartz (SiO₂), probably flint/chert
Likely quartz-rich rock fragment
Probably microcrystalline quartz (SiO₂), possibly a pale chert or quartzite fragment
Chert (or Flint)
Chert (a cryptocrystalline variety of quartz, SiO2)
Chert (Flint)
Microcrystalline quartz (SiO2)
Chert (Nodule/Pebble)
Chert (Silicon Dioxide, SiO2)
Chert (varieties include Flint or Jasper)
Chert (cryptocrystalline quartz; SiO₂)
Chert (or possibly Flint)
SiO2 (Silicon Dioxide)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chalcedony (Quartz Pebbles)
Silicon Dioxide (SiO2)
Chert / River Pebble
Silicon Dioxide (SiO2)
Chert (chalcedony)
Microcrystalline quartz, SiO₂
Iron-stained chert or siliceous sedimentary rock
Microcrystalline quartz (SiO₂), likely chert with iron-oxide staining
Quartz / Chert
Silicon Dioxide (SiO2)
Mookaite Jasper
Siliceous (chert) sedimentary rock, a form of Jasper
Chert (or Flint)
SiO2 (predominantly microcrystalline quartz)
Chert (Tripolitic Chert / Flint Nodules)
Microcrystalline Quartz (SiO2)
Smoky Quartz with Chert
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Rounded flint or chert pebble
Microcrystalline quartz (SiO₂), commonly chalcedony with possible impurities
Tumbled chert or flint pebble
Microcrystalline quartz (SiO₂), likely chert/flint
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Hag Stone
Natural Perforated Flint or Chert (SiO2)
Quartz Pebble (Chert / Chalcedony)
Silicon Dioxide (SiO2)
Chert (Chalcedony/Agate Pebble)
Microcrystalline Quartz (SiO2)
Red jasper (likely iron-rich chert)
Microcrystalline quartz, SiO₂, colored mainly by hematite/goethite
Flint
SiO2 (Cryptocrystalline Quartz)
Flint
Microcrystalline Quartz (SiO2)
Dalmatian Jasper
Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Ironstone Concretion / Chert Nodules
Iron-rich Sedimentary Concretion (Fe2O3 / SiO2 mix)