Mineraloid (Anthropogenic)

Schist (likely Mica Schist)

Mica Schist

Painted beach pebble

Unidentified natural pebble; underlying lithology cannot be determined from the image

Dalmatian jasper (often sold as Dalmatian stone)

Quartz-bearing leucocratic alkali-feldspar–aegirine/arfvedsonite porphyritic rock; commercial “jasper” designation

Granite Cobble

Plutonic Granite

Graphite Schist

C (Carbonaceous Schist)

Pistachio-green and dark mineral-bearing rock, possibly serpentine with dark inclusions

Undetermined; the image is insufficient for reliable species-level identification

Mixed River Pebbles (Jasper, Hematite, and Quartzites)

Silicon dioxide (Jasper/Quartz) and Iron oxide (Hematite)

Possible green tourmaline (small rough crystal fragment)

Possibly elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₄; identification is uncertain from the blurry image

Banding Onyx Marble

Calcite / Travertine

Raw ruby (likely corundum)

Corundum, Al₂O₃; red varieties are ruby

Cat's Eye Moonstone (Feldspar)

Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8) inclusions

Green serpentine pebble (possibly serpentine-rich rock)

Serpentinite, composed chiefly of serpentine-group minerals such as antigorite, lizardite, or chrysotile; exact identification requires testing

Tumbled, mottled stone (possibly jasper or another ornamental rock)

Undetermined from the photograph; visual appearance is insufficient for a reliable species identification

Ironstone concretion (possibly a pyrite-bearing concretion)

Iron-oxide-cemented sedimentary concretion; exact mineral composition cannot be confirmed from the photograph

Bismuth crystal

Bismuth (Bi), commonly laboratory-grown

Polished amber

Fossilized tree resin (primarily organic polymerized diterpenes)

Hag Stone

Sandstone or Limestone with Solution Holes (Bioturbation/Erosion)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Orbicular jasper (likely kambaba jasper)

Silicified microcrystalline quartz and chalcedony with dark-green amphibole or other mafic mineral inclusions; trade name “kambaba jasper”

Small blue-green mineral or stone bead

Unidentified opaque blue-green mineral; the image is insufficient for reliable species identification

Small tumbled stone, likely quartz-rich pebble

Probably microcrystalline quartz (SiO₂), but the image is insufficient for a definitive identification

Small rounded stone or mineral fragment

Indeterminate; likely a common quartz- or feldspar-bearing silicate fragment

Greenstone / Glauconitic Siltstone

Metabasalt or Glauconite-rich Sedimentary Rock

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Gneiss

Quartz–feldspar–mica gneiss

Weathered greenstone (possible serpentinite)

Greenstone, a broad term for metamorphosed mafic rock; exact identification is uncertain from the photograph

Granite (Alkali-feldspar Granite)

Felsic Plutonic Rock (Primary minerals: Quartz SiO2, Orthoclase KAlSi3O8, Plagioclase (Na,Ca)AlSi3O8)

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Pink Granite

Granite (Phaneritic intrusive igneous rock)

Quartzite

Quartzite (primarily SiO2)

Granite (with Orthoclase and Quartz)

Phaneritic Felsic Igneous Rock (KAlSi3O8 + SiO2)

Banded ironstone (likely)

Iron-rich, silica-bearing rock; possibly a fragment of banded iron formation (BIF)

Blue-dyed tumbled stone, likely howlite or magnesite

Likely dyed magnesite (MgCO₃) or howlite (Ca₂B₅SiO₉(OH)₅); identification is uncertain from the image

Limestone or Sandstone Cobble

Sedimentary rock (Calcium carbonate or Quartz based)

Black tourmaline (schorl)

Schorl, NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Rounded iron-rich pebble

Likely ferruginous sandstone or ironstone; exact identification requires testing

Osumilite in Granite Matrix

(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30

Unidentified purple mineral fragment

Possibly amethyst (quartz), but the image is insufficient for confident identification

Serpentinite

Serpentinite, a rock composed mainly of serpentine-group minerals (approximately Mg₃Si₂O₅(OH)₄)

Tumbled serpentine (likely nephrite-like greenstone)

Serpentine-group minerals, chiefly antigorite/lizardite; possibly mixed with tremolite-actinolite

Tumbled serpentine or chlorite-rich pebble

Serpentine-group minerals, chiefly antigorite/lizardite; possibly chlorite or greenstone

Potassium feldspar

Orthoclase or microcline; KAlSi₃O₈