Sedimentary Or Metamorphic (Base Substrate)

Chert (Gravel)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Arkosic Sandstone

Arkose (Clastic Sedimentary Rock)

Crushed Limestone

Sedimentary Carbonate Rock (CaCO3)

Specular Hematite (Specularite)

Iron(III) oxide (Fe2O3)

Gray Limestone Fragment

Limestone (CaCO3)

Chert (likely Flint)

Cryptocrystalline Quartz (SiO2)

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (specifically Gray/Tan Bedded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Weathered brown rock, likely sandstone or iron-rich quartzite

Indeterminate; probable quartz-rich sandstone (quartz, feldspar, iron oxides)

Weathered fine-grained stone, likely sandstone or quartzite

Quartz-rich sandstone (possibly weakly metamorphosed quartzite); predominantly SiO₂

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Mica (Muscovite)

Muscovite, KAl2(AlSi3O10)(OH)2

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 cement)

Sandstone (with Chert/Quartzite)

Arenite (primarily SiO2)

Red Jasper

Microcrystalline Quartz (SiO2)

Pyrite

Iron Sulfide (FeS2)

Garnet in Matrix

Almandine or Pyrope Garnet (X3Y2(SiO4)3) in Schist or Eclogite matrix

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Garnet Amphibolite (or Garnet Gneiss)

Garnet amphibolite / Garnet-bearing metamorphic rock

Fossiliferous Limestone Pebble

Sedimentary Rock (CaCO3)

Quartz Vein in Sandstone

Sandstone with Hydrothermal Quartz (SiO2)

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Sandstone Clast

Arenite (primarily SiO2)

Magnetite-rich ironstone (probable magnetite ore)

Magnetite, Fe₃O₄, likely in a fine-grained ironstone matrix

Pyrite

Iron Pyrite (FeS2)

Pyrite (on the right) and Magnetite or Hematite (on the left)

Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)

Chert or chalcedony fragment (possibly agate)

Microcrystalline quartz, SiO₂

Zebra Jasper

Opaque microcrystalline Quartz (SiO2) with impurities

K2 Jasper (K2 Granite)

Granite with Azurite inclusions (SiO2 + Cu3(CO3)2(OH)2)

Chert (often called Flint)

Microcrystalline Quartz (SiO2)

Dalmatian Jasper

Peralkaline Quartz-Feldspar Porphyritic Rock (Dalmatian Stone)

Limestone

Calcium Carbonate (CaCO3)

Limestone

Limestone (CaCO3)

Banded Slate

Metamorphic Argillite / Slate

Moss-covered Limestone with Quartz/Calcite Pocket

Calcium Carbonate (CaCO3) rock with biological moss coating

Chert

Opaline or Microcrystalline Jasper/Chert (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Field Stone)

Silicon Dioxide (SiO2)

Chert (or Chalcedony) Nodule

Microcrystalline Quartz (SiO2)