Anthropogenic Specimen (Man Made Material)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Granite

Phaneritic plutonic rock (dominated by Quartz, Feldspar, and Mica)

Sandstone

Arenite (primarily SiO2, silica)

Jasper and Quartz conglomerate (River Rock)

Silicon Dioxide (SiO2) - Chalcedony and Quartz variety

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Rose Quartz

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

Chrysocolla Chalcedony

Hydrated Copper Phyllosilicate (Cu,Al)2H2Si2O5(OH)4 + SiO2

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Chert (Jasper/Quartzite variety)

Microcrystalline Silica (SiO2)

Ironstone Concretion (Limonite/Hematite Nodules)

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

Snakeskin Agate

Agate (Cryptocrystalline Quartz, SiO2)

Red Jasper

Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Sandstone

Arenite (primarily SiO2)

Cloudy Quartz

Quartz (Silicon Dioxide, SiO2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Sodalite

Sodalite (Sodium Aluminum Silicate Chloride) - Na8(Al6Si6O24)Cl2

Sandstone

Clastic Sedimentary Rock (composed mostly of SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Mica Schist

Foliated Metamorphic Rock (rich in Muscovite or Biotite)

Quartzite

Quartzite (SiO2)

Chert (Jasper variety)

Microcrystalline quartz (SiO2)

Chert (variations include Flint)

Chert (SiO2)

Blue Chalcedony

Chalcedony (SiO2)

Chert (Brown Variety)

Silicon dioxide (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and Flint)

Silicon Dioxide (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Common Opal)

Silicon Dioxide (SiO2)

Muscovite (White Mica)

Muscovite - Potassium aluminum silicate: KAl2(AlSi3O10)(F,OH)2

Red Porphyry

Porphyritic Andesite or Rhyolite

Chert (White/Light Tan)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Yellow Jasper / Chert

Jasper (Silica/Quartz) - SiO2

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Andesite

Andesite (Intermediate Extrusive Volcanic Rock)

Basalt with Caliche

Extrusive Mafic Igneous Rock with Secondary Carbonate Crust

Chert (Flint)

Microcrystalline Silica (SiO2)

Sandstone

Arenite (primarily Quartz SiO2)

River Stone (River Pebbles)

Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)