Uncertain

Likely rough mineral specimen (possibly mica-rich)

Indeterminate from the image; a mica such as muscovite or biotite is one possibility

Weathered stone nodule or concretion

Unidentified lithic concretion; composition cannot be determined from the image

Likely quartz cabochon in a ring

Quartz (SiO₂), possibly clear or milky quartz; identification is uncertain from the photograph

Weathered, iron-stained rock (likely metamorphic)

Indeterminate from photograph; possibly quartz-rich gneiss or schist

Fossiliferous limestone pebble

Calcite-rich limestone (primarily CaCO₃), with possible fossil or fossil-fragment patterns

Blue-gray stone fragment, possibly slate or fine-grained basalt

Undetermined; appearance is consistent with slate (fine-grained metamorphosed mudstone), but the image is insufficient for reliable identification.

Likely weathered sandstone fragment

Sandstone, chiefly quartz (SiO₂) grains cemented by silica, calcite, or iron oxides

Fine-grained sandstone (tentative)

Quartz-rich sandstone; exact composition cannot be confirmed from the photograph

Dark quartz point (possibly smoky quartz)

Quartz, SiO₂; the dark color may indicate smoky quartz, but the image is insufficient to confirm

Likely polished or naturally smoothed pebble with a pale mineral patch

Undetermined; possibly a dark volcanic rock with a quartz or feldspar inclusion

Tumbled green stone, possibly serpentine or prehnite

Provisional identification: serpentine-group mineral, commonly antigorite; alternatively prehnite or green calcite

Tumbled brown chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Granite or granitic rock

Coarse crystalline felsic intrusive rock, chiefly quartz, feldspar, and mica

Rounded quartz-rich pebble

Likely quartzite or quartz-bearing granitoid; predominantly SiO₂ quartz with possible feldspar and mica

Granite or granitic pebble

Granite; chiefly quartz (SiO₂), feldspar, and mica/amphibole

Tumbled pale-green quartz, likely aventurine or common quartz

Quartz (SiO₂), possibly green aventurine containing fuchsite inclusions

Polished pink stone, possibly rose quartz

Unconfirmed; if rose quartz, silicon dioxide (SiO₂), trigonal quartz

Faceted yellow gemstone, possibly citrine

Unconfirmed; citrine is yellow quartz (SiO₂)

Likely granite pebble

Granite, a quartz–feldspar–mica intrusive igneous rock

Greenstone / serpentinite-like metamorphic rock

Probable serpentinite-rich greenschist; commonly dominated by serpentine-group minerals, chlorite, actinolite, and magnetite

Polished banded stone, likely labradorite or gneiss

Probably feldspar-rich gneiss; possible labradorite-bearing rock (plagioclase feldspar, chiefly (Ca,Na)(Al,Si)₄O₈)

Green aventurine pendant (likely)

Quartz, SiO₂, with green fuchsite inclusions (aventurescent quartz)

Polished chert (likely jasper or iron-rich chert)

Microcrystalline quartz, SiO₂, colored by iron oxides and possibly clay minerals

Unidentifiable Rock Fragment

Pumice

Pumice, a highly vesicular volcanic glass composed mainly of rhyolitic to dacitic silicate material

Likely gneiss

Gneiss, composed chiefly of quartz, feldspar, and mica/amphibole

Small gray stone, possibly granite or quartz-rich pebble

Indeterminate; likely a weathered quartz–feldspar rock fragment

Weathered granite or granitic gneiss

Granite; mainly quartz, feldspar, and mica

Polished yellow chalcedony (likely lemon quartz/calcite alternative)

Microcrystalline quartz, SiO₂ (chalcedony); exact identification requires testing

Dark blue-black polished crystal, likely fluorite or slag-like geological material

Tentatively fluorite (CaF₂); identification is uncertain from the image alone

White pebble, likely quartz or calcite

Indeterminate from image; possible microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Weathered chert or siliceous limestone

Microcrystalline quartz (SiO₂), possibly with carbonate matrix

Mixed polished gemstone bead bracelet, likely tourmalinated quartz and rhyolite/jasper

Quartz (SiO₂) with black tourmaline (schorl, NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄) and probable feldspar-rich rhyolite/jasper

Tumbled greenstone (likely serpentine or chlorite-rich stone)

Serpentinite, approximately Mg₃Si₂O₅(OH)₄; exact identification requires testing

Weathered granite or granitic gravel

Granite; quartz–feldspar–mica aggregate

Clear quartz crystal sphere

Quartz (silicon dioxide, SiO₂)

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image

Unakite (likely)

Epidote–K-feldspar–quartz aggregate; commonly derived from altered granite

Likely botryoidal quartz or calcite cluster

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires hardness and acid tests

Brecciated stone, likely brecciated limestone or marble

Carbonate breccia; chiefly calcite (CaCO₃), with possible dolomite and dark matrix minerals

Hematite (iron oxide)

Hematite, α-Fe₂O₃

Polished amber cabochon pendant

Amber (fossilized plant resin), chiefly polymerized succinite; approximate formula C10H16O