Sedimentary (Man Made Composite)

Sandstone (Ferruginous)

Arenite (with Iron Oxides)

Ferruginous Sandstone with Quartz Inclusions

Clastic Sedimentary Rock (Iron-rich Sandstone)

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Bioclasts

Limestone Pebble

Calcium Carbonate (CaCO3)

Sandstone (with Manganese staining)

Arenite (composed primarily of SiO2)

Fossiliferous Limestone (Bivalve Fossil)

Calcium Carbonate (CaCO3) with Bivalvia fossil

Sandstone (Ferruginous)

Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)

Fluorite

Calcium Fluoride (CaF2)

Weathered granitic rock

Granite or granodiorite; mainly quartz, feldspar, and mica/amphibole

Crushed Limestone

Sedimentary Calcite/Dolomite Rock (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Gravel / Limestone Fragment

Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock

Banded gneiss pebble

Gneiss, chiefly quartz–feldspar–mica with dark biotite/amphibole bands

Flint

SiO2 (Microcrystalline Quartz / Chert)

Sandstone (Siltstone or Fine-grained)

Clastic sedimentary rock (primarily SiO2)

Glauconite (Greensand)

Glauconite (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2

Fossiliferous Limestone

Limestone with fossil bioclasts (Calcium Carbonate, CaCO3)

Shale

Shale (composition varies: primarily clay minerals and quartz)

Quartzite

Quartzite (SiO2)

Sandstone with Iron Oxide

Arenite (SiO2 with Fe2O3 staining)

Chert (Jasper variation)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Sandstone (River Rock)

Arenite (SiO2 principal component)

Fossiliferous Limestone

Biogenic Calcium Carbonate (CaCO3)

Sandstone

Arenite (primarily Quartz Sandstone)

Sandstone (with Arkose characteristics)

Clastic sedimentary rock (SiO2 with KAlSi3O8)

Banded Iron Formation (BIF) / Iron Ore

Banded Iron Formation (composed primarily of Hematite (Fe2O3) and Magnetite (Fe3O4) with Quartz/Chert)

Sandstone (Greywacke)

Sandstone (SiO2 enriched with lithic fragments)

Celadonite in Basalt (Green Earth)

Celadonite (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2)

Conglomerate

Conglomerate (clastic sedimentary rock)

Sandstone

Sedimentary Rock (Quartz Sandstone)

Sandstone

Arenite (Siliclastic Sedimentary Rock)

Limestone with Calcareous Accretion

Sedimentary Carbonate Rock (CaCO3)

Sandstone (Ferruginous)

Clastic Sedimentary Rock (Litharenite)

Mookaite Jasper

Silicified Radiolarite (SiO2)

Chalcedony (variations like Agate or Jasper)

Chalcedony (SiO₂ - microcrystalline quartz)

Quartz Geode

Silicon Dioxide (SiO2) in a sedimentary host

Ferruginous Sandstone

Sandstone, Iron-rich

Barite Rose on Marcasite

Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Chert (Field Stone)

Microcrystalline Quartz (SiO2)

Chalcedony (Agate / Chert)

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions