Uncertain

Iron-stained quartzite cobble

Quartzite, predominantly quartz (SiO₂), colored by iron-oxide coatings or inclusions

Smoky quartz crystal point

Quartz (SiO₂), likely smoky quartz

Chalcedony (likely agate)

Microcrystalline quartz, SiO₂; agate is banded chalcedony

Likely garnet gemstone

Garnet-group silicate; species cannot be determined from the photo (common red varieties include almandine, Fe₃Al₂(SiO₄)₃, and pyrope, Mg₃Al₂(SiO₄)₃).

Rounded quartzite pebble

Quartzite (predominantly recrystallized quartz, SiO₂)

Massive blue-green rough specimen, likely aquamarine (beryl)

Beryl, Be₃Al₂Si₆O₁₈ (tentative identification)

Coarse-grained granite (probable)

Granite, a quartz–feldspar–mica intrusive igneous rock

Iron-stained quartz

Quartz (SiO₂), colored by iron-oxide staining

Tumbled green-brown stone, likely serpentine

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

Yellow-orange calcite specimen

Calcite (calcium carbonate, CaCO₃), likely honey or orange calcite

Faceted colorless gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂), though the strong glare and visible facet pattern could indicate cubic zirconia or lead glass

Clear quartz crystal/chunk

Quartz (silicon dioxide, SiO₂)

Small quartz fragment

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Tumbled pegmatitic rock, likely amazonite-bearing granite

Granite/pegmatite composed mainly of quartz, feldspar, and mica; blue-green area may be microcline (amazonite)

Weathered granite or granitic rock

Granite; chiefly quartz, feldspar, and mica

Weathered granite or granitic rock

Granite; primarily quartz, feldspar, and mica

Likely weathered basalt

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, often with olivine

Mixed tumbled gemstone collection

Varied minerals, likely including amethyst, sodalite/lapis lazuli, quartzite or aventurine, jasper, and agate/chalcedony

Blue sodalite-bearing rock, likely sodalite in nepheline syenite

Sodalite (Na₈Al₆Si₆O₂₄Cl₂), possibly in nepheline syenite

Polished orbicular jasper (likely ocean jasper)

Silicified volcanic rock; chiefly microcrystalline quartz (SiO₂), with feldspar and iron-rich alteration minerals

Rough amber-like brown mineral specimen

Uncertain from photograph; possibly iron-stained quartz, common opal, or resinous amber

Likely mica-rich schist

Mica schist, probably muscovite–biotite schist with quartz and feldspar

Pink halite (rock salt)

Halite (NaCl)

Iron-rich concretion or ironstone nodule

Likely goethite- and/or hematite-cemented ironstone; exact identification requires testing

Brown chalcedony (likely agate)

Microcrystalline quartz, SiO₂; chalcedony, possibly banded agate

Tumbled green stone, likely aventurine

Green aventurine (quartz with fuchsite or other green inclusions), tentatively identified

Calcite crystal

Calcite (CaCO₃)

Botryoidal chalcedony (likely common opal)

Silica, SiO₂; chalcedony is microcrystalline quartz, while opal is hydrated amorphous silica (SiO₂·nH₂O)

Iron-rich laterite (hematitic limonite)

Laterite composed mainly of hematite (Fe₂O₃), goethite (FeO(OH)), and hydrated iron oxides

Chrysoprase-bearing serpentine (probable)

Serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄, with possible nickel-bearing chrysoprase/opal and iron oxides

Likely iron-stained quartz/chalcedony fragment

Quartz (SiO₂), possibly brecciated or partly chalcedonic, with iron-oxide staining

Likely weathered granite or granitic gneiss fragment

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

Probable metallic meteorite fragment

Unclassified iron meteorite candidate, chiefly kamacite (α-Fe–Ni alloy)

Tumbled pale green aventurine or common green quartzite

Quartz, SiO₂, likely with fuchsite or chlorite inclusions

Tumbled green aventurine (likely)

Quartz, SiO₂, with possible fuchsite or other mica inclusions

Dark igneous rock fragment, likely basalt

Basalt; commonly composed of plagioclase, pyroxene, and minor olivine or magnetite

Weathered quartz-rich mineral nodule

Likely quartz (SiO₂) with iron-oxide staining and possibly feldspar/mica; exact identification requires testing

Serpentinized ultramafic rock (likely serpentinite)

Serpentinite; chiefly lizardite, antigorite, and/or chrysotile, commonly with magnetite, chromite, and residual olivine/pyroxene

Colorless faceted gemstone, likely quartz (rock crystal)

Quartz, SiO₂ (identification from image is uncertain)

Rounded gray pebble, likely andesite

Probably andesite; identification from the photo is uncertain

Yellow-orange tumbled stone, possibly calcite

Uncertain from the image; likely calcite (CaCO₃)

Weathered, foliated metamorphic rock (likely schist)

Mica schist, composition uncertain from the photograph