Mixed (Predominantly Sedimentary And Igneous)

Mixed River Pebbles (including Unakite and Jasper)

Polymineralic geological specimens

General river rock or weathered cobble

Mixed rock composition

Red Jasper with Quartz Veining

Microcrystalline Quartz (SiO2)

Concrete fragment with Aggregate

Anthropogenic Concrete with Calcarious and Siliceous Aggregate

Mixed stone-bead bracelet, likely agate/jasper and possibly sodalite or dyed quartz

Primarily microcrystalline quartz (SiO₂) varieties, with opaque iron-rich chalcedony/jasper and probable blue sodalite or dyed material

Granite or Pegmatite with Quartz and Feldspar

Granitoid

Mixed polished river pebbles, predominantly quartzite and quartz

Quartzite (SiO₂), quartz (SiO₂), with possible feldspar-rich and iron-stained lithologies

Silver-colored mica schist

Muscovite–quartz schist, possibly with biotite

Mixed rough mineral specimens, likely quartz-bearing rocks

Probable quartz (SiO₂), with possible feldspar, iron oxides, and altered host rock

Quartz with Mica inclusions (Pegmatite)

Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions

Blue Chalcedony

Silicon Dioxide (SiO2)

Weathered quartz-rich pebble

Likely quartz-rich granitoid (quartz and feldspar); exact identification is uncertain from the image

Weathered conglomeratic volcanic rock

Likely basaltic volcanic breccia or agglomerate, with plagioclase, pyroxene, volcanic glass, and lithic fragments

Tumbled Agate

Silicon Dioxide (Chalcedony variety), SiO2

Mixed polished river stones

Likely quartz, quartzite, chert/jasper, and possibly limestone or marble

Conglomerate

Lithified, poorly sorted gravel; composition is uncertain from the image

River Pebbles (including Granite and Basalt)

Mixed Igneous Rocks (Granite, Basalt)

Soil with Mineral Detritus and Quartz Fragments

Regolith / Silicate Mineral Aggregate

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)

Concrete Fragment

Artificial Conglomerate (Cement and Aggregate)

Unidentified gravel and stone fragments

Mixed, indeterminate lithologies; likely quartz, feldspar, and weathered silicate rock fragments

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Road-surface aggregate (crushed stone)

Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock

Aventurine (Green Quartz)

Silicon Dioxide (SiO2) with inclusions of Fuchsite (Mica)

Mixed gemstone jewelry collection

Various gemstone minerals, including likely amethyst (quartz), sapphire or iolite, garnet, pearl, turquoise, and colored beryl or tourmaline

Pink Granite

Granite (Felsic Plutonic Rock)

Mixed collection of quartz-rich rocks and minerals

Quartz (SiO₂), with some pieces possibly containing feldspar or mica; exact identification is uncertain from the image

Sodalite

Na4Al3(SiO4)3Cl (Sodium Aluminum Silicate Chloride)

Mixed river-worn rock and mineral collection

Mostly quartz/quartzite, feldspar-bearing granitoid, chert, and mafic volcanic rocks; exact species vary by pebble

Asphalt

Asphalt concrete

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Caribbean Calcite

Calcite (CaCO3) with Aragonite (CaCO3)

Migmatite

Migmatite (Mixed metamorphic-igneous rock)

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Mixed Gemstone and Mineral Collection

Mixed Silica and Carbonate minerals (SiO2, CaSO4·2H2O, etc.)

Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)

Mixed Silicates and Sulfides (SiO2, FeS2)

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Weathered rock pebble, possibly sandstone

Likely quartz-rich sandstone; precise identification requires closer examination

Rounded river pebbles, likely basalt and sandstone/conglomerate

Probable basalt (dark specimen) and ferruginous sandstone or weathered conglomerate (tan specimen)

Asphalt (Bituminous Rock)

Natural bitumen or Bituminous limestone/sandstone

Granite

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica