Mineralogical Specimen

Iron-rich laterite or weathered ironstone pebble

Goethite–hematite-rich ferruginous duricrust; commonly approximated as FeO(OH) and Fe₂O₃

Tumbled greenstone (probable serpentinite)

Serpentinite, chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), possibly with chlorite, magnetite, or talc

Tumbled gray stone, likely serpentinite or weathered basalt

Tentatively serpentinite (predominantly serpentine-group minerals); identification is uncertain from the photograph

Manganese Dendrite on Siltstone

Manganese Oxide (pyrolusite or psilomelane) Dendrites

Pyrite Sun (Pyrite Dollar)

Iron Disulfide (FeS2)

Tumbled greenstone/serpentinite pebble

Serpentinite, chiefly antigorite/lizardite Mg₃Si₂O₅(OH)₄; identification is visual and uncertain

Geode with Quartz/Chalcedony

Silicon Dioxide (SiO2)

Serpentine-rich greenstone (probable serpentine/soapstone fragment)

Serpentine-group minerals, chiefly antigorite/lizardite; possibly minor talc, chlorite, and carbonate

Polished blue-green feldspar-rich slab, likely amazonite

Amazonite, green microcline (KAlSi₃O₈), possibly with quartz and albite inclusions

Blue glass-like tumbled specimen

Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image

Likely graphite-rich schist (possibly galena-bearing metamorphic rock)

Graphite schist; chiefly quartz–mica with graphite (identification uncertain from photograph)

Tumbled mica-rich stone, likely muscovite schist

Muscovite-bearing quartz schist; chiefly muscovite mica, quartz, and possibly feldspar

Polished serpentine-rich stone

Serpentinite, primarily serpentine-group minerals (antigorite, lizardite, or chrysotile)

Serpentinite (likely serpentinized ultramafic rock)

Serpentine-group minerals, chiefly antigorite/lizardite; commonly derived from peridotite

Serpentinite (probable)

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

Serpentinite

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

Metallic sulfide-bearing metamorphic rock

Likely graphitic schist or sulfide-rich schist, with possible pyrite/arsenopyrite and mica

Blue-green raw mineral specimen, likely apatite

Fluorapatite, Ca₅(PO₄)₃F (probable; visual identification only)

Petrified Wood

Silicified Wood (SiO2)

Polished orbicular gabbro tower

Gabbro, likely orbicular/pegmatitic variety; mainly plagioclase feldspar and pyroxene, with possible amphibole, olivine, and magnetite

Dalmatian jasper (likely orbicular microgranite)

Quartz–feldspar–biotite/pyroxene microgranite; commonly marketed as Dalmatian jasper

Dendritic Quartz

Silicon Dioxide (SiO2) with Manganese Oxide inclusions

Polished banded calcite/aragonite tower

Calcite (CaCO₃), possibly aragonite (CaCO₃)

Serpentinite (likely antigorite-rich)

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

Dalmatian jasper

Quartz-bearing, orbicular microcrystalline silica (commonly sold as “Dalmatian jasper”; often an altered porphyritic igneous rock)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Malachite-bearing copper ore

Malachite (Cu₂CO₃(OH)₂), likely mixed with chrysocolla, limonite, or native copper minerals

Weathered greenstone / serpentinite (probable)

Serpentinite, chiefly antigorite–lizardite Mg₃Si₂O₅(OH)₄; possibly altered mafic greenstone

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

Limonite/goethite mixture (hydrated iron oxides), composition uncertain from image

Labradorite

(Ca, Na)(Al, Si)4O8 (Calcium Sodium Aluminum Silicate)

Tumbled serpentine (likely nephrite-like greenstone)

Serpentine-group minerals, chiefly antigorite/lizardite; possibly mixed with tremolite-actinolite

Uncertain dark gray-brown rock fragment

Indeterminate; possibly weathered chert, serpentine, or iron-stained quartzite

Blue-dyed tumbled stone, likely howlite or magnesite

Likely dyed magnesite (MgCO₃) or howlite (Ca₂B₅SiO₉(OH)₅); identification is uncertain from the image

Fossilized oyster shell in limestone

Bivalvia fossil; chiefly calcite (CaCO₃)

Mixed River Pebbles (Jasper, Hematite, and Quartzites)

Silicon dioxide (Jasper/Quartz) and Iron oxide (Hematite)

Polished green jasper cabochon (likely serpentine or nephrite imitation)

Jasper: microcrystalline quartz (SiO₂); green coloration may reflect chlorite, epidote, or iron minerals

Possible green tourmaline (small rough crystal fragment)

Possibly elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₄; identification is uncertain from the blurry image

Optical Calcite

Calcium Carbonate (CaCO3)

Sand Grain (Quartz)

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (containing Plagioclase, Quartz, and Biotite)

Granitic Gneiss

Gneiss (High-grade metamorphic rock)

Granite

Phaneritic Plutonic Felsic Rock