Sedimentary And Igneous (Mixed)

Conglomeratic breccia

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

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)

Sandstone with Desert Varnish

Arenite with Ferromanganese patina

Tumbled purple-blue corundum, possibly sapphire

Corundum (Al₂O₃); blue-to-purple varieties are sapphire

Diorite

Intermediate Phaneritic Igneous Rock

Agate (Lake Superior Agate variant)

Chalcedony / Silicon Dioxide (SiO2)

Sodalite and Calcite

Na8(Al6Si6O24)Cl2 (Sodalite) and CaCO3 (Calcite)

Pegmatite

Igneous Pegmatite (Quartz, Feldspar, Micas)

African Turquoise

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

Conglomerate

Polymictic conglomerate, likely carbonate-cemented

Weathered iron-rich rock, possibly hematite-bearing chert

Hematite (Fe₂O₃), likely mixed with silica and iron oxides

Mixed Gravel and Pebbles

Polylithic Alluvial Aggregate

Lunar Meteorite

Lunar Feldspathic Breccia

Pink Granite

Phaneritic Quartz-Feldspar Plutonic Rock

Pegmatite

Granitic Pegmatite

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Polymict conglomerate (pebble conglomerate)

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

Polished granite pebble

Granite; chiefly quartz, feldspar, and mica/amphibole

Pink and Green Tourmaline (Tumbled)

Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4)

Quartz-rich metamorphic rock, likely mica schist

Mica schist; chiefly quartz (SiO₂) and mica, likely muscovite/biotite, with possible feldspar

Graphite

Graphite (Carbon, C)

Banded Amethyst

Silicon Dioxide (SiO2) with iron impurities

Jasper-Quartz Conglomerate / Chert

Siliceous Sedimentary Rock (SiO2)

Mixed rock and mineral collection

Multiple specimens; visible examples may include quartz (SiO₂), amethyst (quartz), calcite (CaCO₃), and dark mafic rocks

Diorite (River Rock/Cobble)

Intermediate Plutonic Igneous Rock (Diorite)

Pink Granite

Granite (Phaneritic Acidic Igneous Rock)

Sodalite

Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)

Gray granite or granitic gneiss gravel

Granite; primarily quartz, feldspar, and mica (exact identification is uncertain from the photograph)

Granodiorite

Granodiorite (intermediate intrusive igneous rock containing plagioclase, quartz, and K-feldspar)

Quartz-bearing feldspar pegmatite (likely with mica/tourmaline)

Granitic pegmatite; chiefly quartz (SiO₂) and feldspar, with dark mica or tourmaline

Granite pebble

Granite; primarily quartz, alkali feldspar, plagioclase, and dark mica/amphibole

Polished/rounded granite cobble

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

River gravel and cobbles

Mixed alluvial clasts, likely including granite, basalt, quartzite, and sandstone

Polished quartz-rich feldspar rock, possibly orbicular granite

Granite or granitic pegmatite; chiefly quartz (SiO₂), feldspar, and dark biotite/amphibole

Rainbow Hematite (Man-made/Treated)

Tumbled Hematite with Titanium/Anodized coating (Iron(III) oxide, Fe2O3)

Tumbled banded stone, likely gneiss or granite

Quartz–feldspar rock, possibly banded gneiss; exact identification requires testing

Barite

Barium Sulfate (BaSO4)

Unidentified coarse-grained rock fragments

Likely granite or granitic rock; exact identification is uncertain from the photograph

Feldspar (Granite Pegmatite matrix)

Potassium Feldspar (KAlSi3O8) / Quartz Mixture

Conglomerate

Conglomerate (clastic sedimentary rock)