Mixed (Igneous, Sedimentary, Metamorphic, And Minerals)

Epidosite

Epidosite (composed primarily of Epidote and Quartz)

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Dalmatian Jasper

Microcrystalline Quartz with Arfvedsonite/Tourmaline inclusions

Peacock Ore

Bornite (Cu5FeS4)

Feldspar

Feldspar (Orthoclase/Microcline)

Bauxite (Iron-stained Chert / Ironstone Aggregate)

Hydrous aluminum oxide mixture (mainly Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Goethite α-Fe3+O(OH))

Gneiss or Schist

Gneiss or Mica Schist with Garnet

General river rock or weathered cobble

Mixed rock composition

Quartz vein fragment

Quartz, silicon dioxide (SiO₂), likely milky to translucent quartz with iron-oxide or clay inclusions

Quartz-rich rock, possibly milky quartz or quartzite

Quartz (SiO₂); if quartzite, recrystallized quartz sandstone

Likely quartz-rich stone (possibly milky quartz or quartzite)

Quartz, silicon dioxide (SiO₂), or quartzite if interlocking grains are present

Mixed garnet crystal specimens

Garnet-group silicates, likely almandine–spessartine with possible grossular/pyrope varieties; general formula X₃Y₂(SiO₄)₃

Fuchsite on Quartz

Muscovite (KAl2(AlSi3O10)(OH)2) with Chromium impurities

African Turquoise

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

Dalmatian Stone (commonly called Dalmatian Jasper)

Peralkaline Rock (mixed Feldspar, Quartz, and Arfvedsonite)

Mixed rough mineral specimens, likely quartz-bearing rocks

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

Yellow Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Glacially transported granite and gneiss boulders

Granite (quartz–feldspar–mica); banded specimens likely gneiss

Fancy Jasper

Silicon Dioxide (SiO2) with iron and organic inclusions

Green Aventurine

SiO2

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Vesuvianite (Idocrase)

Vesuvianite, Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4

Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Assorted Tumbled Gemstones

Mixed oxides and silicates (including Quartz, Chalcedony, and Feldspar variants)

Weathered granitic rock fragment

Likely granite or granodiorite; quartz–feldspar–mica aggregate

Weathered polymictic rock fragment, likely granite-rich conglomerate

Indeterminate mixed lithology; apparent granitic clasts containing quartz, feldspar, and dark mafic minerals

Pyrite-bearing sulfide specimen

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

Black granite (likely polished gabbro or diabase)

Granitoid rock dominated by feldspar, quartz, and dark mafic minerals; exact identification requires testing

Mixed gravel and mineral fragments

Polymictic unconsolidated sediment; likely quartz, feldspar, chert, mica, and lithic fragments

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

Galena

Lead Sulfide (PbS)

Polished/tumbled rhodonite-rich stone

Rhodonite (MnSiO₃), likely mixed with quartz and manganese oxides

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

Blue-green tumbled stone, possibly chrysocolla-bearing material

Uncertain from image; likely chrysocolla (hydrated copper silicate, variably written Cu₂H₂Si₂O₅(OH)₄·nH₂O), possibly mixed with quartz or other copper minerals

Concrete-like aggregate surface with embedded rock fragments

Anthropogenic concrete or exposed aggregate; not a natural rock specimen

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Metallic sulfide mineral specimen, likely pyrite-bearing ore

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

Magnetite / Ironstone

Magnetite (Fe3O4)

Magnetite Ore

Magnetite (Fe3O4)

Mixed Polished Gemstones (Tumbled Stones)

Mixed Silicates and Oxides (SiO2, KAlSi3O8, Ca2Al2Be3Si6O22, etc.)

Quartz geode

Microcrystalline and crystalline quartz, SiO₂, likely with chalcedony and iron-oxide staining

Lapis Lazuli

Lapis Lazuli (a rock composed primarily of Lazurite)