Mineraloid (Cryptocrystalline Quartz)

Chert (Chalky/Gray Variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Nodule)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (variably Oolitic or Fossiliferous)

Sedimentary Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fancy Jasper

Chalcedony (cryptocrystalline quartz) with inclusions

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Chert (variant Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Chert (Flint nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert

Sedimentary Cryptocrystalline Quartz (SiO2)

Chert (with Iron Staining)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Blue Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint variety)

Chert (Cryptocrystalline Quartz, SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Yellow or River Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chalcedony (Agate/Jasper mix)

Cryptocrystalline Sillimanite (Quartz) - SiO2

Chert (Nodule)

Silicon Dioxide (SiO2)

Jasper with Quartz Vein

Microcrystalline quartz (SiO2) with quartz infill

Tumbled white quartz pebble

Quartz (silicon dioxide, SiO₂)

Tumbled yellow chalcedony (probable)

Chalcedony, microcrystalline quartz (SiO₂), possibly iron-stained jasper

Quartz (likely a form of massive or vein quartz)

Quartz (SiO₂)

Chert with Quartz Vein

Microcrystalline Quartz (SiO2) with Macrocrystalline Quartz

Tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂), likely colored by iron oxides

Tumbled brown stone, likely jasper or iron-rich chert

Microcrystalline quartz (SiO₂), possibly iron-oxide-bearing jasper/chert

Polished blue lace agate slice

Chalcedony (microcrystalline quartz), SiO₂, commonly with blue-gray banding and a druzy quartz center

Polished smoky quartz or brown chalcedony pebble

Silicon dioxide (SiO₂), likely quartz/chalcedony with iron-oxide inclusions

Blue Chalcedony

Silicon dioxide (SiO2)

Jasper

Silicon dioxide (SiO2)

Chalcedony geode or quartz-rich agate nodule

Microcrystalline quartz, SiO₂, with possible crystalline quartz druse

Carnelian Agate

Silicon dioxide (SiO2) with iron impurities

Chert or flint fragment

Microcrystalline quartz (SiO₂), commonly called chalcedony or flint

Chalcedony (Common Opal variant or Chert/Flint)

Silicon Dioxide (SiO2)

Jasper

Silicon Dioxide (SiO2) with impurities (mostly Iron Oxides)

Chalcedony (Common Opal variant or Quartz)

Silicon Dioxide (SiO2)

Jasper

Silicon dioxide (SiO2)