Industrial Byproduct (Anthropogenic Material)

Yellow Jasper

Silicon Dioxide (SiO2) - Opaque variety of Chalcedony/Quartz

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Breccia

Breccia - Clastic sedimentary rock

Sandstone

Arenite (SiO2-rich)

Mica Schist

Mica Schist (Main mineral constituents: Muscovite/Biotite, Quartz, Feldspar)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Ferruginous Sandstone Pebble

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH) staining)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Siltstone with flute casts or scratch marks

Clastic Sedimentary Rock (Siltstone/Fine-grained Sandstone)

Porphyritic Andesite

Andesite (porphyritic variety)

Chalk

Carbonate rock (mainly CaCO3)

Banded Flint (Chert)

Silicon Dioxide (SiO2)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Quartz Geode

Silicon Dioxide (SiO2)

Sandstone (Red/Brown Variety)

Arenite (SiO2 with iron oxide impurities)

Graphic Granite

Pegmatitic Feldspar with Quartz intergrowths

Green Quartzite (with Fuchsite)

Quartzite with Muscovite variety Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

Sandstone (likely Arkosic or Quartzose)

Sandstone (SiO2 with inclusions)

Red Sandstone

Arenite (predominantly Quartz with Hematite cementation)

Conglomerate

Conglomerate (Sedimentary rock containing rounded clasts)

Red Jasper (Mahogany Obsidian variant similarity)

Silicon Dioxide (SiO2) with iron oxide inclusions

Scoria

Vesicular Basalt / Scoria

Sandstone

Arenite (primarily Quartz, SiO2)

Sandstone (Ferruginous)

Arenite (with iron oxide cement, Fe2O3)

Yellow Jasper

Silicon Dioxide with iron inclusions (SiO2)

Chert (Flint)

Cryptocrystalline Silica (SiO2)

Banded Iron Formation (Jaspillite)

Banded Iron Formation (BIF) / Jaspillite

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Satin Spar Selenite

Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)

Sandstone

Clastic Sedimentary Rock (primarily SiO2)

River Stone / Siltstone

Siltstone (composed of lithified silt)

Chert (Jasper/Ironstone variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Fossiliferous Limestone (Coquina / Shell Conglomerate)

Bioclastic Limestone (composed primarily of CaCO3)

Diorite (River Cobble)

Intrusive Igneous Diorite

River Cobble (Quartzite and Iron-stained Quartz)

Quartzite (SiO2 with iron oxide impurities)

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)

Granite

Phaneritic Felsic Igneous Rock (primarily Quartz, Alkali Feldspar, and Plagioclase)

Olivine in Basalt matrix

Peridotite (Mg, Fe)2SiO4

Basalt (River Pebble)

Basalt

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)