Mineraloid (Man Made)

Tumbled greenstone / serpentinite (probable)

Serpentinite, chiefly Mg-rich serpentine minerals (antigorite, lizardite, chrysotile), possibly mixed with chlorite, magnetite, or carbonate

Diamond

Carbon (C)

Diamond

Carbon (C)

Mixed stone-bead bracelet, likely agate/jasper and possibly sodalite or dyed quartz

Primarily microcrystalline quartz (SiO₂) varieties, with opaque iron-rich chalcedony/jasper and probable blue sodalite or dyed material

Coal (Anthracite / Bituminous)

Organic Sedimentary Rock (Carbon-based)

Inscribed limestone fragment

Calcitic limestone (primarily CaCO₃), possibly marble if recrystallized

Chert / Green Jasper

Silicon Dioxide (SiO2)

Polished green-inclusion stone, likely chlorite-included quartz

Quartz (SiO₂) with chlorite inclusions; exact identification is uncertain from the photograph

Likely lateritic ironstone (limonite/goethite-rich)

Goethite, α-FeO(OH), with possible limonite and clay impurities

Beaded blue-and-green gemstone jewelry

Likely dyed or treated chalcedony/agate and green aventurine or glass-like stone; exact identification requires testing

Vesicular Rhyolite

Rhyolite (High-silica volcanic rock)

Serpentinite (probable)

Serpentinite, dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with dark magnetite or chromite and pale carbonate/talc possible

Green Banded Chert (Agate/Jasper)

Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite

Possible iron-rich meteorite

Provisional: stony-iron or iron meteorite; mineralogy may include kamacite (α-Fe,Ni) and taenite (γ-Fe,Ni)

Polished black stone, likely basalt or black jasper

Indeterminate; possible fine-grained basalt (plagioclase–pyroxene) or black jasper/microcrystalline quartz

Gemstone bead necklace (likely citrine or yellow quartz)

Quartz, SiO₂; precise identification is uncertain because the beads are blurred and metal settings obscure them

Amethyst bead bracelet

Amethyst, purple quartz (SiO₂), with likely dyed or heat-treated agate/carnelian beads

Weathered metallic fragment, possibly iron meteorite or industrial slag

Uncertain; candidate iron meteorite (Fe–Ni alloy), but terrestrial slag or corroded metal is also plausible

Tumbled sodalite (probable)

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂; possibly blue-dyed jasper or lapis lazuli

Native Silver

Silver (Ag)

Tumbled mica-rich stone, likely muscovite schist

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

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Fossilized coral with attached shell

Likely fossil coral (Scleractinia or Tabulata), with a bivalve or gastropod shell; exact identification requires microscopy

Polished blue-green feldspar-rich slab, likely amazonite

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

Slag (Industrial Glass Slag)

Amorphous Silicate Glass (often containing Al, Ca, Mg, and Ti oxides)

Raw calcite specimen

Calcite, calcium carbonate (CaCO₃)

Green tourmaline (likely elbaite)

Tourmaline-group cyclosilicate; likely elbaite, Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

Chert (or Flint)

Chert (cryptocrystalline quartz), SiO2

Tumbled chalcedony (likely blue-gray agate)

Cryptocrystalline quartz, SiO₂; chalcedony/agate variety

Gneiss

Gneiss (a type of metamorphic rock)

Cobalt Blue Sea Glass

Amorphous Silica Glass (SiO2 + CoO)

Ruby-in-Fuchsite cabochon/tower

Corundum (ruby, Al₂O₃) in fuchsite-bearing mica schist; commonly with chromite and quartz

Iron Slag

Ferrous Slag (Industrial Byproduct)

Carved smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), smoky variety

Clear quartz crystal pendant

Quartz (silicon dioxide, SiO₂)

Vesicular basalt (likely)

Basalt; chiefly plagioclase, clinopyroxene, and olivine, with possible iron-oxide alteration

Likely basalt

Mafic volcanic rock, chiefly plagioclase and pyroxene, commonly with minor olivine and magnetite

Marble

Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Mother of Pearl (Nacre)

Calcium Carbonate (primarily aragonite, with conchiolin)

Polished red jasper cabochon

Jasper; microcrystalline quartz (SiO₂) with iron-oxide impurities

Orbicular basalt (amygdaloidal basalt)

Basalt, commonly with iron-oxide–stained amygdules; matrix chiefly plagioclase, pyroxene, and often olivine