Man Made Object (Coin)

Likely polished blue-green stone bead or small gemstone

Uncertain from the photo; possibly dyed or treated agate/chalcedony, but identification requires testing

Tumbled blue stone, likely blue aventurine or dyed quartzite

Quartz (SiO₂), likely with inclusions or artificial dye; exact identification requires testing

Heart-shaped Pebble (Limestone/Quartz)

Calcium Carbonate (CaCO3) / Silicon Dioxide (SiO2)

Amber (Black)

Amber (succinite, retinite, etc., specifically, heavily included/dark varieties)

Possible fossil tooth or bone fragment

Indeterminate fossilized vertebrate material; species cannot be identified reliably from this image

Weathered mica-rich schist

Muscovite/biotite schist, likely quartz-bearing

Weathered quartz-rich pebble

Likely granitic or felsic igneous rock; quartz (SiO₂) with feldspar and minor mafic minerals

Polished citrine quartz point

Quartz, silicon dioxide (SiO₂), yellow-orange variety commonly sold as citrine; possibly heat-treated amethyst

Spiny Oyster Shell

Spondylus varians (Biogenic Calcium Carbonate)

Diamond (or Diamond Simulant)

Carbon (C)

Blue opalite (often sold as synthetic opal)

Opalite glass; amorphous hydrated silica if natural opal (SiO₂·nH₂O)

Polished operculum (“Shiva eye” shell)

Calcium-carbonate shell operculum, commonly from a turban snail (family Turbinidae); not a mineral specimen

Copper Nugget

Native Copper (Cu)

Gemstone-set ring, likely cubic zirconia or diamond

Likely synthetic cubic zirconia (zirconium dioxide, ZrO₂); stones may alternatively be diamond (carbon, C)

Jadeite Jade

Jadeite (NaAlSi2O6)

Quartz-rich stone tool or shaped mineral specimen

Likely milky quartz or quartzite (SiO₂); exact material cannot be confirmed from the image

Likely polished dark stone (identity uncertain)

Undetermined; possibly polished basalt, chert, or another dark silicate rock

Likely polished dark stone or mineral specimen (unidentifiable from image)

Undetermined; possibly dark quartz-rich material, basalt, or obsidian

Likely biotite-rich mica schist

Mica schist, chiefly biotite (K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂); exact identification from image is uncertain

Black-and-copper polished granite

Biotite granite, likely a commercial gabbro/granite variety

Calcite

Calcite (CaCO₃, Calcium Carbonate)

Weathered limestone pebble

Limestone, chiefly calcite (CaCO₃)

Petrified Wood

Silicified wood (primarily SiO2)

Green glassy mineral specimen, likely rough emerald or green fluorite

Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph

Limestone

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Diamond (in jewelry setting)

Diamond (C - Carbon)

Tumbled orange calcite

Calcite (CaCO₃)

Selenite (gypsum crystal)

Gypsum, CaSO₄·2H₂O; monoclinic crystal

Calcite crystal cluster

Calcite, CaCO₃

Blue calcite

Calcite (CaCO₃)

Polished rose quartz bowl

Quartz, silicon dioxide (SiO₂), likely rose quartz

Colorless faceted gemstone, likely glass or quartz

Uncertain; appearance is consistent with faceted quartz (SiO₂), but cut glass or cubic zirconia cannot be excluded from the photograph

Fossil gastropod shell

Fossilized marine gastropod; exact genus/species requires locality and examination

Polished mahogany obsidian

Volcanic glass (mostly SiO₂), commonly called mahogany obsidian

Optical Calcite

Calcite (Calcium Carbonate, CaCO3)

Banded agate pendant (likely carnelian or brown-and-white chalcedony agate)

Agate, a banded variety of chalcedony; microcrystalline quartz, SiO₂, with iron-oxide coloration

Carrara Marble

Recrystallized Calcite (CaCO3)

Green Calcite

Calcium Carbonate (CaCO3) with trace impurities

Blue Celestite

Celestine (SrSO4)

Quartz with Calcite

Silicon Dioxide (SiO2) / Calcium Carbonate (CaCO3)

Native Gold Nugget

Gold (Au)