Mixed (Predominantly Sedimentary And Igneous)

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Pyrite

Iron Sulfide (FeS2)

Quartz-rich conglomeratic sandstone

Lithic arkose/conglomerate, dominated by quartz and feldspar grains

Mixed gravel and small stones

Unsorted gravel; individual clasts are not identifiable from the image

Mixed collection of small rounded pebbles

Unidentified river- or beach-worn lithic clasts; individual rock types cannot be determined confidently from the image

Mixed rounded river gravel

Polymictic alluvial gravel; likely mixtures of quartzite, granite, basalt, sandstone, and other silicate rocks

River Cobble (Mixed Lithology)

Clastic Sedimentary Rock (Silicified Siltstone or Wacke)

Mixed River Pebbles and Jasper

Siliciclastic sediment and microcrystalline quartz

Paving-concrete aggregate with a rounded stone

Polymictic gravel aggregate; the central clast appears to be weathered sandstone or volcanic rock

Quartz (Engineered Stone Countertop)

Silicon Dioxide (SiO2) with polymer resins

Milky Quartz

Silicon Dioxide (SiO2)

Pink Granite

Phaneritic intrusive igneous rock with dominant Alkali Feldspar

Rainbow Hematite (Man-made/Treated)

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

Granite

Intrusive Igneous Rock

Granite

Intrusive Igneous Rock

Lapis Lazuli

Lapis Lazuli (Complex rock primarily composed of Lazurite (Na,Ca)8[(SO4,S,Cl)2|(AlSiO4)6], Calcite, and Pyrite)

Iron-rich concretion (likely limonite/goethite)

Limonite–goethite aggregate; commonly hydrated iron oxides, approximately FeO(OH)·nH₂O

Vesicular basalt (likely scoria)

Vesicular basalt; predominantly plagioclase, pyroxene, and possibly olivine

Mixed polished rock/mineral specimens

Indeterminate from image; likely quartz-bearing material with iron-oxide staining and possibly mica-rich schist

Limonite

FeO(OH)·nH2O

Black Onyx

Cryptocrystalline quartz (SiO2)

Red Jasper

Silicon Dioxide (SiO2) - variety of Chalcedony

Iron-rich sandstone or ferruginous conglomeratic sandstone

Ferruginous sandstone, primarily quartz (SiO₂) cemented or stained by iron oxides/hydroxides

Conglomeratic sandstone / breccia-like gravel rock

Polymictic conglomerate (possibly lithified gravel or concrete-like natural conglomerate)

Banded Iron Formation (BIF) / Iron Ore

Hematite-Magnetite BIF (Fe2O3 / Fe3O4 mixed with SiO2)

Pyrite-bearing sulfide ore

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

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Mixed mineral and gemstone specimens

Likely amethyst (quartz), malachite, blue calcite or dyed chalcedony, red jasper, and green aventurine/serpentine

Granite (Pink/Red Granite)

Phaneritic Felsic Igneous Rock

Citrine

Silicon dioxide (SiO2)

Red garnet-bearing metamorphic rock

Almandine garnet (Fe₃Al₂Si₃O₁₂), likely in mica schist or quartz-rich matrix

Mixed mineral and rock collection, including likely amethyst and assorted tumbled stones

Unidentified mixed specimens; visible purple quartz is likely amethyst (SiO₂)

Mixed mineral and rock specimen collection

Assorted silicates, carbonates, oxides, and sulfides; individual species cannot be reliably identified from this image

Labradorite

(Na, Ca)(Si, Al)4O8

Beaded gemstone bracelet, likely amethyst and mixed polished stones

Amethyst: quartz (SiO₂); other beads appear to be assorted quartz/chalcedony or jasper

Granite with Quartz/Pegmatite

Intrusive Igneous Rock

Conglomerate (Greenstone/Pebble Conglomerate)

Polymictic Conglomerate

Banded metamorphic rock, likely gneiss

Gneiss; predominantly quartz–feldspar with mica/amphibole minerals

Tumbled chert or flint

Microcrystalline quartz (SiO₂), commonly chalcedony with possible iron-oxide inclusions

Mixed small mineral specimens

Likely quartz varieties with possible rose quartz and iron-stained quartz; exact identification is uncertain from the blurred image

Unidentifiable Specimen

Undetermined

Ironstone Pebble

Ferruginous sedimentary rock (Fe2O3 / FeO(OH) mixed with SiO2)