Mixed

Azurite–malachite-bearing quartz or chalcedony

Cu₃(CO₃)₂(OH)₂ azurite with Cu₂CO₃(OH)₂ malachite in SiO₂-rich matrix

Rounded river pebble

Likely lithic sandstone or weathered quartz-rich rock; exact identification requires testing

Mixed rock and mineral collection

Mixed lithologies; likely quartz, feldspar, basalt, granite, chert, sandstone, and metamorphic rocks

Conglomeratic breccia

Clast-supported polymictic conglomerate/breccia, cemented by silica- or carbonate-rich matrix

Polished brown jasper

Jasper (microcrystalline quartz, SiO₂), likely iron-oxide-rich variety

Mixed river gravel (alluvial conglomeratic sediment)

Polymictic alluvium; composition includes quartz, feldspar, chert, granite, basalt, and metamorphic rock fragments

Bauxite

Aluminium ore (Hydrated aluminium oxides AlOx(OH)3-2x)

Jasper and Quartz Breccia

Silica breccia (SiO2)

Sandstone with Desert Varnish

Arenite with Ferromanganese patina

Mixed rough mineral specimens, likely calcite with prehnite/zeolite

Calcite (CaCO₃), with probable prehnite (Ca₂Al₂Si₃O₁₀(OH)₂) and/or zeolite-group minerals

Mixed polished gemstones and minerals

Likely agate/chalcedony (SiO₂), quartz, jasper, and possibly aventurine or obsidian; exact identification requires individual testing.

Graphite

Graphite (Native Carbon, C)

Mixed River Stones and Agates

Mixed Silicates and Ironstones (primarily SiO2 and Fe2O3)

Polished mixed rock, likely orbicular/epidote-bearing granite or basalt

Uncertain; probable quartz–feldspar–amphibole/epidote aggregate

Polymict conglomerate (pebble conglomerate)

Clastic sedimentary rock; rounded pebble and granule clasts in a finer-grained matrix

Likely weathered granite or granitic rock

Granite; quartz + feldspar + mica, compositionally variable

Tumbled brown-black stone, likely smoky quartz or iron-stained agate

Indeterminate from image; possible quartz (SiO₂), chalcedony, or iron-rich jasper

Granite pebble

Coarse-grained granitic rock, primarily quartz–feldspar–biotite

African Turquoise

African Turquoise (a trade name for Jasper, a variety of Chalcedony: SiO2)

Granodiorite

Intermediate Phaneritic Plutonic Rock

Granite

Granite (Felsic Plutonic Rock)

Conglomeratic gravel / lithified alluvial deposit

Polymictic conglomerate or pebble-rich sandstone (likely weakly cemented)

Likely gabbro or diabase

Mafic igneous rock, chiefly plagioclase feldspar and pyroxene; possible olivine and amphibole

Likely weathered granite or granitic gneiss

Granite: quartz + feldspar + mica; possibly gneiss if the faint banding is structural

Biotite-bearing mica schist (probable)

Mica schist, chiefly quartz + muscovite/biotite; composition is uncertain from the photograph

Granite Pebble (Pegmatitic Quartz-Feldspar River Rock)

Granite / Quartz-Feldspar-Mica Aggregate

Amethyst (Chevron or Banded Amethyst)

Silicon Dioxide (SiO2) with Fe3+ impurities

Red Granite

Granite (Felsic Plutonic Rock)

Landscaping stones

Unidentified natural fieldstones, possibly granite, gneiss, quartzite, and limestone

Blue glassy fragment among beach gravel

Likely cobalt-blue man-made glass; not a natural mineral specimen

Fossiliferous Shale Matrix

Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments

Asphalt (Bituminous pavement)

Bituminous concrete / Asphalt

Mixed gemstone bead strand, likely including agate, quartz, turquoise, and sandstone beads

Varied silicate and copper-mineral materials; exact bead identities cannot be confirmed visually

Dyed, polished stone beads (likely assorted agate or jasper)

Microcrystalline quartz, SiO₂ (chalcedony; exact stones cannot be determined from the image)

Chrysocolla with Malachite

Cu2-xAlx(H2-xSi2O5)(OH)4%CnH2O (Chrysocolla)

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Chrysocolla (carved)

Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)

Pink Granite

Phaneritic Felsic Igneous Rock

Banded River Cobble with Mafic Dike

Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion

Mahogany Obsidian

Volcanic Glass (SiO2 with Hematite/Magnetite inclusions)

Unakite

Unakite (altered granite)

Azurite Malachite

Azurite (Cu3(CO3)2(OH)2) and Malachite (Cu2CO3(OH)2)