Synthetic Or Natural Fiber

Tumbled amber

Fossilized tree resin; commonly succinite (organic resin, not a mineral)

Tumbled chalcopyrite (likely)

Chalcopyrite, CuFeS₂

Tumbled brecciated jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions

Tumbled quartzite or quartz-rich stone

Quartzite; predominantly microcrystalline quartz (SiO₂)

Tumbled quartz-rich pebble

Quartz (SiO₂), possibly iron-stained or included quartz

Tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂) with iron-oxide inclusions

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Tumbled yellow chalcedony (likely citrine or yellow jasper)

Microcrystalline quartz, SiO₂; exact identification is uncertain from the photograph

Tumbled cream chalcedony or quartz

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony

Flint (Chert)

Silicon Dioxide (SiO2)

Quartzite (River Stone)

Quartzite (SiO2)

Blue Dyed Quartzite

Silicon Dioxide (SiO2) with artificial pigment

Blue Calcite

Calcium Carbonate (CaCO3)

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminum)

Citrine

SiO2 (Silicon Dioxide)

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Tumbled quartz-rich pebble, likely milky quartz with iron-oxide staining

Quartz (SiO₂), possibly with hematite/goethite inclusions or surface coating

Tumbled jasper, likely red jasper

Microcrystalline quartz (SiO₂), chalcedony variety with iron-oxide impurities

Likely tumbled orange-brown jasper or chert

Microcrystalline quartz (SiO₂), probably iron-oxide-bearing jasper

Flint (chert), likely a worked or fractured nodule

Microcrystalline quartz/chalcedony (SiO₂)

Greenstone / serpentine-rich metamorphic rock

Likely serpentinite, composed mainly of serpentine-group minerals (antigorite, lizardite, or chrysotile), with possible magnetite and chlorite

Tumbled blue chalcedony (likely blue quartz/chalcedony)

Cryptocrystalline silica, SiO₂; likely chalcedony, possibly dyed or surface-coated

Polished dark green stone, likely nephrite jade

Nephrite jade (interlocking tremolite–actinolite amphibole, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)

Tumbled yellow chalcedony (likely citrine or yellow jasper)

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony

Polished ocean jasper (orbicular jasper), probable

Microcrystalline quartz (SiO₂), chiefly chalcedony with iron-oxide and other mineral inclusions

Tumbled dark gray stone, likely basalt

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Tumbled pink quartz (probable rose quartz)

Quartz, silicon dioxide (SiO₂), likely rose quartz

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)

Silicon Dioxide (SiO2) with iron inclusions

Yellow Quartz (Citrine or Yellow Chalcedony)

Silicon Dioxide (SiO2)

Tumbled yellow granite or granitic gneiss

Granite, chiefly quartz, feldspar, and biotite/amphibole

Tumbled chalcedony (likely moss or dendritic agate)

Microcrystalline quartz, SiO₂, with iron-oxide inclusions

Polished banded limestone or marble pebble

Calcite-rich carbonate rock (CaCO₃), possibly banded marble

Tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂), likely colored by iron oxides

Tumbled black tourmaline

Schorl tourmaline, NaFe3Al6(BO3)3Si6O18(OH)4

Tumbled reddish-brown jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides

Tumbled jasper, likely red/brown jasper

Microcrystalline quartz (chalcedony), SiO₂, colored chiefly by iron oxides

Tumbled green-blue stone, likely serpentine or chlorite-rich metamorphic rock

Serpentinite (mainly antigorite/lizardite; identification is image-based)

Tumbled feldspar–quartz rock, possibly granite or pegmatite

Feldspar (orthoclase/plagioclase) + quartz, with dark biotite or hornblende

Milky quartz (possibly pale rose quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled quartz-rich pebble

Quartz (SiO₂), likely with iron-oxide staining and minor feldspar

Tumbled jasper or chert

Microcrystalline quartz (SiO₂), possibly iron-bearing jasper

Banded limestone or marble

Calcite-dominated carbonate rock; likely banded marble (CaCO₃)