Organic Mineraloid

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Jasper

Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Chert (Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Stromatolite (Jasper-replaced)

Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)

Grey and White Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Petrified Wood

Silicified Wood (SiO2)

Chert (Quartz Variety)

Microcrystalline Silica (SiO2)

Chert (specifically Tan/Yellow Chert)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Chert (Flint Pebbles)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Yellow Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions

Fossil Coral (Favosites Honeycomb)

Favosites (Genus), Phylum Cnidaria, Class Anthozoa

Petrified Wood

Silicified Wood (SiO2)

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Septarian Nodule

Septarian Concretion

Chert (White/Light Tan)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2)

Chert (Nodular)

Chert (SiO2 - Microcrystalline Quartz)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (specifically Tan/Brown Chert)

Chert (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Jasper

Jasper (Silicon Dioxide, SiO2)

Banded Chert (Jasper)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Glauconitic Sandstone (or Greensand)

Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Green Jasper (with Quartz veining)

Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2

Banded Chert

Microcrystalline Quartz (SiO2)

Jasper (likely Brown or Brecciated)

Jasper (Silicon Dioxide, SiO2)

Banded Chert

Cryptocrystalline Quartz (SiO2)

Red Jasper

Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)