Mixed (Predominantly Sedimentary And Igneous)

Fossiliferous Shale Matrix

Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments

Mixed rock and mineral collection

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

Mixed beach-stone and tumbled-glass collection

Predominantly uncertain rocks (likely basalt, granite, and quartz-bearing stones) with anthropogenic glass; one possible banded agate or jasper

Weathered iron-rich rock, possibly hematite-bearing chert

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

Rounded porous volcanic rock (likely scoria)

Scoria, vesicular basalt

Pegmatite

Granitic Pegmatite

Mixed Gemstones and Minerals

Mixed Silicates and Oxides (Quartz/Amethyst, Aventurine, Sodalite, Chert, Jasper)

Carnelian and Mixed Agates

Cryptocrystalline Quartz (SiO2 with Iron Oxide impurities)

Mixed River Stones and Agates

Mixed Silicates and Ironstones (primarily SiO2 and Fe2O3)

Metallic sulfide mineral specimen, likely pyrite-bearing ore

Likely pyrite (FeS₂), possibly mixed with other sulfides or host rock

Quartz-rich metamorphic rock, likely mica schist

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

Quartz-bearing rock fragment

Likely milky quartz with iron-oxide staining and possible host-rock minerals; exact identification is uncertain from the image.

Polymict conglomerate (pebble conglomerate)

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

River gravel and cobbles

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

Sandstone (likely Greywacke or Siltstone variety)

Arenite / Siltstone (primarily SiO2)

Green Gneiss

Metamorphic Gneiss

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Jasper-Quartz Conglomerate / Chert

Siliceous Sedimentary Rock (SiO2)

Granite Pebble

Granite

Nuummite

Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)

Yellow Chalcedony (Agate)

Silicon Dioxide (SiO2)

Asphalt fragment

Bituminous concrete

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Conglomerate

Conglomerate (clastic sedimentary rock)

Banded Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amethyst

Amethyst (SiO2 - Silicon Dioxide with iron impurities)

Orange Calcite

Calcium Carbonate (CaCO3)

Polished granite pebble

Granite; chiefly quartz, feldspar, and mica/amphibole

Diorite (River Rock/Cobble)

Intermediate Plutonic Igneous Rock (Diorite)

Pink Granite

Granite (Phaneritic Acidic Igneous Rock)

Concrete-like aggregate surface with embedded rock fragments

Anthropogenic concrete or exposed aggregate; not a natural rock specimen

Likely iron-rich river cobble (weathered basalt or ironstone)

Indeterminate; possibly weathered basalt, with hematite/goethite staining

Pink and Green Tourmaline (Tumbled)

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

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)

Sandstone (lithic wake/graywacke variety)

Arenite/Greywacke (SiO2 with lithic fragments)

Jasper (Green Jasper/Heliotropic Chert)

Silicon Dioxide (SiO₂)

Quartz-rich pegmatite (likely rose/iron-stained quartz)

Quartz, SiO₂, in a coarse granitic pegmatite matrix; possibly with feldspar and mica

Mixed rough mineral specimens, likely calcite with prehnite/zeolite

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

Barite

Barium Sulfate (BaSO4)

Sodalite

Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)

Epidote (Unakite variety)

Epidosite (Metasomatic rock containing Ca2(Al,Fe)3(SiO4)3(OH))