Anthropogenic Material

Amphibolite

Hornblende–plagioclase amphibolite

Tumbled granite (likely granodiorite)

Granite–granodiorite aggregate, chiefly quartz, feldspar, and biotite/hornblende

Likely quartz-rich rock or weathered granite fragment

Granite-like quartz–feldspar aggregate; exact identification requires testing

Coquina / Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate - CaCO3)

Red Sandstone

Arenite (with Iron Oxide cement)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)

Quartz Sand

Silicon Dioxide (SiO2)

Crushed Limestone

Calcium Carbonate (CaCO3)

Fossiliferous Sandstone / Fossil Fragment

Fossiliferous Sedimentary Matrix with Indeterminate Fossil Material

Unakite

Epidotized Granite

Tiffany Stone

Fluorite-bearing Opalized Breccia

Likely serpentine-rich metamorphic rock

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile), with possible magnetite and minor chlorite/talc

Polished fossiliferous limestone

Bioclastic limestone, chiefly calcite (CaCO₃)

Serpentinite (likely)

Serpentinite, dominated by serpentine-group minerals (chrysotile, lizardite, or antigorite), commonly with magnetite and relict olivine/pyroxene

Weathered iron-rich quartz or limonite-bearing stone

Quartz (SiO₂) with iron-oxide/hydroxide coatings, likely goethite–limonite

Greenstone / Serpentinite Pebble

Serpentinite (Hydrated Magnesium Silicate, Mg3Si2O5(OH)4)

Serpentinite (serpentine-rich rock)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, chlorite, and talc

Schist

Mica schist, likely muscovite–biotite schist with quartz and feldspar

Concrete with Aggregate

Artificial Conglomerate (Cement and Aggregate)

Blue-green turquoise (probable)

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Petrified Wood

Silicified Wood (primarily SiO2)

Jasper

Silicon Dioxide (SiO2) with impurities

Fossilized Nut / Coprolite / Concretion

Trace Fossil / Permineralized Plant Material

Mottled gabbro or diorite pebble

Coarse-grained mafic/intermediate intrusive rock; chiefly plagioclase feldspar plus pyroxene, with possible amphibole or biotite

Greenstone or Metabasalt

Metabasalt / Chlorite Schist

Sandstone

Arenite (SiO2 primarily)

Jasper / Chert (tumbled/water-worn)

Microcrystalline Quartz (SiO2)

Agate

Cryptocrystalline quartz, Chalcedony (SiO2)

Sandstone

Arenite (SiO2 primarily)

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone Pebble

Sandstone (primarily Quartz, SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Red Sandstone or Brick Fragment

Arenite (if sandstone)

Tree Agate

Silicon dioxide (SiO2)

Asphalt (Road Aggregate)

Bituminous conglomerate

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of organic matter)

Petrified Wood

Silicified Wood (primarily SiO2)

Zircon

Zirconium Silicate (ZrSiO₄)

Serpentinite

Serpentinite; chiefly serpentine-group minerals (lizardite, antigorite, chrysotile), often with magnetite and minor brucite

Greenschist

Greenschist (chlorite schist)

Orbicular jasper

Orbicular jasper (microcrystalline quartz/chalcedony with iron-oxide and volcanic inclusions)