Mineralogical Simulant

Likely weathered iron-rich sandstone or laterite

Ferruginous sandstone; predominantly quartz (SiO₂) cemented or stained by iron oxides such as hematite (Fe₂O₃) and goethite (FeO(OH))

Iron-stained sandstone

Quartz arenite or lithic sandstone, variably cemented by iron oxides

Sapphire

Corundum (Al2O3)

Likely metallic meteorite fragment

Undetermined iron or stony-iron meteorite; mineralogy requires testing

Diamond (Set in jewelry)

Cubic Carbon (C)

Banded Calcite (commonly traded as Green Onyx / Travertine Onyx)

Calcite (CaCO3) / Travertine

Likely basalt pebble

Basalt, a fine-grained mafic volcanic rock; commonly composed of plagioclase, pyroxene, and sometimes olivine

Weathered sandstone block

Quartz-rich sandstone, likely arkose or calcareous sandstone

Banded quartzite pebble

Quartzite, predominantly quartz (SiO₂), with orange iron-oxide staining

Weathered iron-rich concretion or breccia

Goethite/hematite-bearing limonite concretion, possibly ferruginous sandstone

Weathered iron-rich sandstone or ironstone

Ferruginous sandstone, likely limonite/goethite-cemented quartz arenite

Small brown rock fragment

Undetermined; possibly weathered iron-stained quartzite or chert

Greenstone (probable altered basalt)

Chlorite–epidote–actinolite-rich greenschist; composition commonly derived from basalt

Pyrite-bearing quartz or sulfide-rich rock

Pyrite (FeS₂) in quartz-rich matrix, possibly with chalcopyrite

Diamond (in Jewelry)

Diamond (Carbon, C)

Colorless faceted gemstone, likely cubic zirconia

Cubic zirconia (zirconium dioxide, ZrO₂); visual confirmation is unavailable

Iron-rich concretion or weathered ironstone nodule

Goethite–hematite-rich limonite concretion (tentative)

Polished red jasper cabochon

Jasper; microcrystalline quartz (SiO₂) with iron-oxide impurities

Granite (Dioritic or Hornblende-rich)

Phaneritic Plutonic Felsic to Intermediate Igneous Rock

Opalite (a synthetic glass)

Silicon Dioxide (SiO2) with various additives; not a true mineral but a man-made gem simulant

Conglomeratic breccia (possibly polymictic volcanic breccia)

Polymictic breccia; clasts in a fine-grained volcanic or sedimentary matrix

Fossilized bivalve shell

Bivalvia indeterminate; likely a preserved clam or cockle shell, composed mainly of calcium carbonate (CaCO₃)

Iron-rich weathered rock, possibly limonite/goethite-bearing ore

Limonite (hydrated iron oxides; chiefly goethite, FeO(OH), with hematite and other oxides possible)

Brick

Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)

Weathered quartz-rich rock, possibly chert or quartzite

Indeterminate; likely microcrystalline quartz (SiO₂), possibly quartzite or chert

Granite

Felsic intrusive igneous rock

Sea stack

Likely resistant basaltic to andesitic volcanic rock

Granite

Granite

Orbicular basalt (amygdaloidal basalt)

Basalt, commonly with iron-oxide–stained amygdules; matrix chiefly plagioclase, pyroxene, and often olivine

Hypersthene

(Mg,Fe)SiO3 - Enstatite-Ferrosilite series

Rounded river pebble, likely quartz-rich stone

Unidentified lithic clast; exact mineralogy cannot be determined from the image

Likely iron-rich metamorphic rock (possibly hematite-rich ironstone)

Unidentified ferruginous rock; exact mineralogy cannot be determined from the image

Rounded iron-rich concretion or weathered lateritic pebble

Goethite/hematite-bearing ferruginous concretion; exact mineralogy requires testing

Concretion (likely iron-rich sandstone or claystone concretion)

Diagenetic carbonate/iron-oxide concretion; exact mineralogy requires testing

Desert Rose Fragment (Atypical) / Weathered Chert

Silicon Dioxide (SiO2) or Barium Sulfate (BaSO4) depending on exact mineralogy

Banded Gneiss

Gneiss (Metamorphic rock of variable mineralogy, often quartz-feldspar base)

Chrysoprase- or serpentine-bearing quartz vein with pyrite

Quartz (SiO₂) with iron sulfide, chiefly pyrite (FeS₂), in altered Mg-rich rock; green material may be serpentine or nickel-bearing chalcedony

Green schist (probable)

Chlorite–mica schist; exact mineralogy cannot be confirmed from the photograph

Weathered foliated metamorphic rock, likely schist or gneiss

Micaceous quartz–feldspar metamorphic rock; exact mineralogy requires testing

Ocean Jasper (Orbicular Jasper)

Silica (SiO2) with varied mineral inclusions

Chert (specifically Silex or Flint)

Microcrystalline Quartz (SiO2)

Violet faceted gemstone, likely synthetic or simulant

Indeterminate from the image; possible violet sapphire (corundum, Al₂O₃), amethyst (quartz, SiO₂), or glass/another simulant