Anthropogenic (Man Made Industrial Byproduct)

Quartzite

Metamorphic Rock (Mainly SiO2)

Diabase (Greenstone)

Diabase (Dolerite)

Iron-rich meteorite candidate

Unclassified iron meteorite or stony-iron meteorite; confirmation requires chemical and nickel testing

Sandstone

Arenite

Diamond (Pear Cut)

Carbon (C)

Quartz-lined vesicle in basalt (amygdaloidal basalt)

Amygdaloidal basalt with drusy quartz; predominantly plagioclase, pyroxene, and iron oxides

Ferruginous Sandstone (Ironstone)

Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

Limestone

Calcareous sedimentary rock (CaCO3)

Talc

Talc (Mg₃Si₄O₁₀(OH)₂)

Weathered iron-rich rock, possibly jasper or ironstone

Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests

Red Sandstone

Arenite (with Iron Oxide / Hematite staining)

Uncertain polymict breccia or altered volcanic rock

Likely hydrothermally altered volcanic breccia; exact mineral identification requires testing

Chert (Yellow Jasper variant)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Dyed Blue Agate Slice

Silicon Dioxide (SiO2)

Banded Calcite or Travertine

Calcium Carbonate (CaCO3)

Chalcedony (Agate Pebble)

Silicon Dioxide (SiO2)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Quartz-veined weathered host rock

Quartz (SiO₂) in a likely altered limestone or metamorphic carbonate host

Fossil brachiopod or bivalve shell

Likely a fossilized brachiopod; precise genus cannot be determined from the photograph

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Epidote

Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH))

Sandstone (Quartzite-rich)

Clastic Sedimentary Rock (primarily SiO2)

Iron-rich meteorite candidate

Unclassified stony-iron or iron meteorite fragment

Iron-rich quartzite or ironstone fragment

Quartzite dominated by quartz (SiO₂), with iron oxides such as hematite/goethite

Red Jasper

Silicon dioxide (Microcrystalline Quartz, SiO2)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Granite

Granite (felsic intrusive igneous rock)

Polished orbicular jasper

Jasper, a microcrystalline variety of quartz (SiO₂), colored by iron oxides and other accessory minerals

Banded sandstone pebble

Quartz-rich sandstone, likely iron-oxide- and organic/mineral-stained; exact variety uncertain

Green Fluorite

Calcium Fluoride (CaF2)

River Stone (Limestone)

Sedimentary Calcium Carbonate (CaCO3)

Likely small metallic meteorite fragments

Unclassified iron or stony-iron meteorite; mineralogy cannot be confirmed from the image

Green Fluorite

Calcium Fluoride (CaF2)

Weathered iron-rich concretion (probable limonite/goethite)

Limonite–goethite aggregate, approximately FeO(OH)·nH₂O

Granite

Granite (Felsic Plutonic Rock)

Rhodonite-bearing rock

Rhodonite (MnSiO₃), likely with manganese oxides and quartz

Limestone

Calcium Carbonate (CaCO3)

Limonite (Iron Ore)

Hydrous Iron Oxide (goethite, lepidocrocite)

Granite Cobble/Pebble

Granite

Native copper (probable copper-rich mineral specimen)

Copper, Cu; possibly mixed with cuprite, malachite, and iron-oxide alteration minerals

Granite

Granite (composed primarily of Quartz, Feldspar, and Mica/Amphibole)