Sedimentary Rock (Possibly Conglomerate Or Breccia With A Quartz Vein)

Milky Quartz

Silicon Dioxide (SiO2)

Polished brecciated jasper (likely orbicular/picture jasper)

Microcrystalline quartz/chalcedony (SiO₂) with iron-oxide staining and breccia fragments

Clear Quartz

Silicon Dioxide (SiO2)

Weathered iron-rich sandstone or laterite

Ferruginous sandstone; potentially lateritic ironstone, composed mainly of quartz (SiO₂) with iron oxides/hydroxides

Calcite (likely honey/orange calcite)

Calcite — calcium carbonate, CaCO₃

Tumbled blue stone, likely blue aventurine or dyed quartz

Quartz (SiO₂), possibly with fuchsite inclusions; exact identification requires testing

Quartzite River Rock

Quartzite (SiO2)

Concrete with Exposed Aggregate

Anthropogenic conglomerate (Concrete)

Weathered iron-rich rock, possibly laterite or limonite-bearing sandstone

Laterite/limonite-rich material; commonly dominated by goethite (FeO(OH)) and hydrated iron oxides

Weathered iron-rich rock, possibly limonite-bearing sandstone or laterite

Limonite/goethite-rich ferruginous rock; exact identification requires testing

Yellow Chalcedony (Carnelian / Agate Pebbles)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Weathered granite or granitic gneiss

Quartz–feldspar–mica granitoid; possibly gneiss if the visible layering is tectonic

Metallic sulfide mineral specimen, likely pyrite

Pyrite (FeS₂), possibly a pyrite-rich sulfide aggregate

Greywacke (Stream Pebble with Quartz/Calcite Veins)

Greywacke sandstone / Metagraywacke

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Fossiliferous limestone, possibly containing a brachiopod or bivalve fossil

Calcite-rich limestone (CaCO₃), with an apparent shell impression or shell fragment

Quartz-bearing rock or quartz-rich mineral specimen

Quartz, silicon dioxide (SiO₂); exact host rock is uncertain from the image

Pyrite on Quartz matrix

Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)

Quartz

Silicon dioxide (SiO2)

Chert (Yellow or Tan Chert)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Green aventurine quartzite (likely)

Quartz-rich metamorphic rock; predominantly microcrystalline quartz (SiO₂), with possible fuchsite, chlorite, or epidote

Polished amber-colored stone, possibly chert or jasper

Uncertain from image; likely microcrystalline quartz (SiO₂) if chert/jasper

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Jasper

Microcrystalline Quartz (SiO2)

Blue mineral specimen, likely bornite (“peacock ore”)

Bornite, Cu5FeS4, possibly iridescent chalcopyrite (CuFeS2)

Quartz (Milky/Common Quartz)

Silicon Dioxide (SiO2)

Unakite-like granite with a white feldspar inclusion

Granite, chiefly quartz–feldspar–biotite; pale inclusion likely albite/orthoclase feldspar

White Quartz

Silicon Dioxide (SiO2)

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (likely Clear Quartz or Rock Crystal)

Quartz (SiO2)

Fossilized tooth, likely a mammalian tooth fragment

Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth

Ocean Jasper

Orbicular Jasper (Silicon Dioxide, SiO2)

Milky Quartz

Quartz (Silica / Silicon Dioxide), SiO2

Fossil Shell Fragment (possibly Brachiopod or Bivalve)

Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca

Quartz

Silicon Dioxide (SiO2)

Limestone with Quartz or Calcite Veining

Calcium Carbonate (CaCO3) matrix with SiO2 or CaCO3 inclusions