Mixed (Predominantly Sedimentary And Igneous)

Peacock Ore

Bornite (Cu5FeS4)

Weathered metallic sulfide-bearing rock, possibly pyrite-rich ore

Tentatively pyrite (FeS₂) with iron oxides and host rock; exact identification requires testing

Pegmatite with Quartz and Feldspar

Intrusive Igneous Rock

Pea Gravel / River Gravel

Unconsolidated Clastic Sedimentary Aggregate

Tumbled orbicular granite

Granite, commonly biotite–quartz–feldspar granite with orbicular or mafic enclaves

Mixed collection of polished pebbles, including probable fossiliferous limestone

Unidentified sedimentary rocks; the gray pebble with circular fossils may be bioclastic limestone

Rounded river pebbles (mixed lithologies)

Water-worn clasts; individual stones cannot be identified precisely from the image

Mixed limestone and sandstone specimens

Mostly calcitic limestone (CaCO₃), with possible quartz-rich sandstone and iron-oxide staining

Mixed gravelly conglomeratic road aggregate

Polymictic clast-supported conglomerate or fill; composition varies, commonly quartz, feldspar, basalt, and weathered rock fragments

Mixed river gravel, prominently iron-stained chert/jasper

Microcrystalline quartz (SiO₂), chiefly chert/jasper with iron-oxide staining; mixed clasts may include quartzite and other silicates

Jasper and Mixed River Pebbles

Microcrystalline Quartz (Chalcedony / Jasper)

Likely quartz-bearing metamorphic pebble

Indeterminate; probable quartzite or quartz-rich gneiss with dark mica/amphibole

Jasper and Basalt (Mixed Breccia or Chert)

Silicon Dioxide (SiO2) with Ferromagnesian silicates

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Weathered iron-rich rock, possibly hematite-bearing breccia

Hematite (Fe₂O₃)-rich lithic fragment; exact host rock is uncertain from the image

Mixed rock specimens; likely pink feldspar/quartz and a dark, mica-bearing rock

Tentative visual identification: pink K-feldspar–quartz-rich granite/pegmatite fragments and a dark amphibole- or biotite-rich metamorphic rock; exact identification is uncertain from the image

Mixed rock fragments, likely basalt and weathered granite

Probable mafic volcanic rock (basalt) with granitoid fragments; exact identification is uncertain from the image

Mixed rounded cobbles, likely granite and weathered volcanic rock

Granite and probable andesite/basalt clasts; exact identification is uncertain from the photograph

Faceted gemstones, likely mixed small sapphires or spinel

Corundum (Al₂O₃) or spinel (MgAl₂O₄); exact identification requires testing

Rutilated Quartz

Rutile in Quartz (SiO2 with TiO2 inclusions)

K-Feldspar (Microcline / Orthoclase)

Potassium Feldspar (KAlSi3O8)

Ocean Jasper

Orbicular Jasper / Silicate

Sandstone

Arenite (predominantly SiO2)

Quartz-rich metamorphic rock, likely mica schist or quartzite

Quartz (SiO₂) with mica, feldspar, and possibly iron-oxide staining

Citrine

Silicon Dioxide (SiO2)

Pink Granite (Crystalline Granite)

Igneous Intrusive Rock (Felsic Plutonic)

Sandstone

Arenite (SiO2 predominantly)

Yellow Quartz (Citrine or Yellow Chalcedony)

Silicon Dioxide (SiO2)

Botryoidal chalcedony (possibly agate/geode material)

Chalcedony, microcrystalline quartz (SiO₂)

Quartz Geode (with Agate banding)

Silicon Dioxide (SiO2)

Rounded, foliated metamorphic pebble (likely schist)

Mica schist, composition uncertain from the image

Raw tourmaline crystal (probable schorl)

Tourmaline group; likely schorl, NaFe3+Al6(BO3)3Si6O18(OH)4

Mixed polished and tumbled mineral specimens, prominently amethyst

Amethyst: purple quartz, SiO₂; accompanying pieces may include jasper, agate, aventurine, tiger’s eye, and other lapidary stones

Mixed quartz gemstone bead bracelet

Quartz, silicon dioxide (SiO₂), in varieties including smoky quartz, amethyst, rutilated quartz, and possibly tourmalinated quartz

Mixed rock and mineral collection

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

Sandstone

Arenite (SiO2 predominantly)

Weathered conglomerate pebble

Polymictic conglomerate, likely quartz- and feldspar-rich clasts in a cemented matrix

Banded Iron Formation (Jaspilite / Hematite Jasper)

SiO2 + Fe2O3 (Quartz with Hematite/Magnetite)

Sandstone (Flagstone)

Arenite (predominantly SiO2)

Sandstone

Arenite (SiO2 predominantly)

Tumbled hematite (likely hematite-rich ironstone)

Hematite, Fe₂O₃; possibly mixed with magnetite or goethite

Polished granite or granitic gneiss pebble

Granite; chiefly quartz, feldspar, and mica/amphibole