Mineraloid Like Synthetic Material

Chert (containing Quartz)

Microcrystalline Silica (SiO2)

Sandstone (likely Fossiliferous)

Arenite / Sedimentum arenaceum

Bauxite

Bauxite (Al(OH)3, AlO(OH))

Polygenetic Breccia

Clastic Breccia (containing lithic fragments in a fine-grained matrix)

Quartz Mica Schist

Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)

Banded Onyx (Mexican Onyx / Travertine)

Calcite (CaCO3) - Banded Travertine

Chert / Flint

Microcrystalline or cryptocrystalline quartz (SiO2)

Chert (Nodular or Massive Variety)

Cryptocrystalline Quartz (SiO2)

Rhodonite (in matrix)

Rhodonite (Mn,Fe,Mg,Ca)SiO3

Banded Chert

Microcrystalline Quartz (SiO2)

Chert / Flint

Cryptocrystalline Quartz (Silicon Dioxide, SiO2)

Petrified Wood

Silicified wood (Quartz, SiO2)

Sandstone (with Iron Staining)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Mookaite (Mookaite Jasper)

Silicified Radiolarite (SiO2 with iron oxides)

Quartzite with Hematite

Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 inclusions)

Chert (Banded)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Fossil Coral (Favosites Honeycomb)

Favosites (Genus), Phylum Cnidaria, Class Anthozoa

Aventurine (specifically Green Aventurine)

Silicon Dioxide (Quartz) with inclusions of Fuchsite; SiO2 + K(Al,Cr)2AlSi3O10(OH)2

Quartz-veined Siltstone

Siltstone with Quartz (SiO2) veins

Ferruginous Sandstone

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

Chert (Jasper/Quartzite river stone)

Microcrystalline Silicon Dioxide (SiO2)

Granite

Phaneritic intrusive igneous rock (consisting mainly of Quartz, Alkali Feldspar, and Plagioclase)

Chalcedony (Common Opal or Agate variant)

Silicon Dioxide (SiO₂)

Sandstone Chert/Quartzite

Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite

Granite

Phaneritic Felsic Igneous Rock (Granite)

Halite

Sodium Chloride (NaCl)

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Chert (often called Flint or Jasper depending on color)

Chert (SiO2 - Microcrystalline or Cryptocrystalline Quartz)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Tektite (Indochinite)

Tektite (High-silica natural glass)

Coquina

Biogenic Limestone (Calcitic shells)

Sandstone

Arenite (primarily SiO2)

Scoria

Vesicular Basalt / Scoriaceous Basalt

Sandstone (with banding/weathering)

Clastic Sedimentary Rock (primarily SiO2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Green Onyx (Banded Calcite)

Travertine (CaCO3 - Calcium Carbonate)

Jasper

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)

Sandstone (likely Ferruginous)

Arenite (SiO2 based with Fe2O3/FeO(OH) cement)