Mixed (Predominantly Sedimentary And Igneous)

River Rocks and Pebbles

Mixed Silica-rich Sediments (SiO2 based)

Bauxite

Bauxite (Al2O3·2H2O mixed with iron oxides)

Granite Cobble

Phaneritic Felsic Igneous Rock (Granite)

Garnet crystals

Garnet-group silicates, likely almandine (Fe₃Al₂Si₃O₁₂)

Greywacke

Lithic Sandstone (Greywacke)

Brick

Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)

Quartz geode

Microcrystalline and crystalline quartz, SiO₂, likely with chalcedony and iron-oxide staining

Glauconitic Sandstone

Glauconitic Sandstone (Quartz with Glauconite)

Dalmatian Jasper

Peralkaline rhyolite

Yellow Jasper

Jasper (Silicon Dioxide with Iron Hydroxide impurities, SiO2 + FeO(OH))

Rounded weathered stone, likely basaltic or volcanic rock

Indeterminate fine-grained mafic volcanic rock; possibly basalt or andesite

Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Vesuvianite (Idocrase)

Vesuvianite, Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4

Granite and Mixed Landscape Gravel

Plutonic Igneous Rock / Weathered Alluvium

Garnet

Group of silicate minerals (e.g., Almandine: Fe3Al2(SiO4)3)

Epidosite

Epidosite (composed primarily of Epidote and Quartz)

Weathered granitic rock fragment

Likely granite or granodiorite; quartz–feldspar–mica aggregate

Turquoise

Turquoise - CuAl6(PO4)4(OH)8·4H2O

Mixed tumbled gemstone chips

Polychrome jasper, quartz/chalcedony, feldspar, and other silicate fragments (exact identification requires testing)

Mixed Mineral Assortment (Pyrite, Kyanite, Agate, Jasper)

FeS2 (Pyrite), Al2SiO5 (Kyanite), SiO2 (Agate/Jasper)

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

Pyrite in Matrix (Healers Gold / Pyrite Egg)

Iron Disulfide (FeS2) with Magnetite/Hematite matrix

Limonite (Ironstone Concretion)

Limonite (Hydrous Ferric Oxides mixed with Goethite)

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles

Mixed gemstones (primarily Silicon Dioxide - SiO2)

Olivine in Quartz/Feldspar Matrix (Peridotite or Granitic Pegmatite)

(Mg,Fe)2SiO4 (Olivine) with Quartz / Feldspar

River Pebbles (White Quartz and Basalt mix)

Mixed Clastic Sedimentary Assemblage (SiO2 and Mafic Volcanics)

Sandstone and Mixed Rock Assemblage

Clastic Sedimentary Rock / Quartz Arenite

Polished/tumbled metallic sulfide specimen, likely pyrite

Pyrite (FeS₂), possibly mixed with chalcopyrite or other sulfides

Bumblebee Jasper

Anhydrite with Sulfur, Hematite, and Orpiment (SiO2/CaSO4 mixture)

Mixed beach gravel and cobbles

Polylithic alluvial or littoral clasts, including quartz, quartzite, chert, limestone, sandstone, and flint

Polished black stone, likely obsidian or dark basalt

Volcanic glass (obsidian), possibly basalt; exact identification requires testing

Conglomerate

Conglomerate (clastic sedimentary rock)

Mixed rounded rock pebbles

Likely granitic gneiss, basaltic rock, and quartz-rich granitic material; exact identification is uncertain from the image

Pyrite in Quartz

FeS2 (Iron Pyrite) with SiO2 (Quartz)

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Mixed sandstone and iron-rich sedimentary rock fragments

Quartz arenite/subarkose, with ferruginous cement and possible iron-oxide staining

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Rounded gravel / river pebbles

Polymictic alluvial gravel, commonly quartz-, feldspar-, and lithic-rich clasts

Iron-stained quartz-rich rock (possibly ironstone or ochre-coated quartz)

Undetermined ferruginous rock; yellow-brown coloration likely from goethite and/or limonite (hydrated iron oxides)

Asphalt / Bituminous Aggregate

Bituminous mixture (Hydrocarbon-based sediment)

Mixed garnet crystal specimens

Garnet-group silicates, likely almandine–spessartine with possible grossular/pyrope varieties; general formula X₃Y₂(SiO₄)₃

Likely quartz-rich gravel fragment (uncertain identification)

Quartz, silicon dioxide (SiO₂), possibly mixed with feldspar or other light-colored minerals