Synthetic Or Natural Fiber

Tumbled opalite (likely man-made glass)

Opalite, a trade name for opalescent glass; not natural opal

Tumbled honey calcite (probable)

Calcite — calcium carbonate, CaCO₃

Tumbled granite or granitic gneiss

Granite, primarily quartz, alkali feldspar, plagioclase, and dark biotite/amphibole

Yellow Quartz / Citrine Quartz

Silicon Dioxide (SiO2)

Carved yellow chalcedony (likely citrine-colored quartz or agate)

Microcrystalline quartz, SiO₂; chalcedony/agate variety, possibly heat-treated or dyed

Tumbled quartz-rich stone, possibly citrine or iron-stained quartz

Quartz (SiO₂), likely limonite/goethite inclusions

Polished brown chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration

Tumbled agate

Microcrystalline quartz (SiO₂), chiefly chalcedony with possible translucent quartz bands

Tumbled white quartz pebble

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Rounded iron-rich concretion or weathered sandstone pebble

Goethite/hematite-bearing sandstone or limonite concretion; exact identification requires testing

Weathered sandstone or siltstone pebble

Clastic sedimentary rock, likely quartz-rich sandstone (dominantly SiO₂)

Tumbled pale limestone or calcite-rich stone

Limestone, chiefly calcite (CaCO₃); exact identification is uncertain from the photograph

Quartz (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine Quartz)

Silicon Dioxide (SiO2)

Tumbled orange calcite

Calcite (calcium carbonate, CaCO₃)

Tumbled honey calcite

Calcite (calcium carbonate, CaCO₃)

Tumbled pale-yellow quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled granitic rock, possibly granite pegmatite

Granite or granitic pegmatite; chiefly quartz, feldspar, and mica, with possible iron-oxide staining

Amber (Sumatran / Indonesian Red Blue)

Succinum (Fossilized Tree Resin)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Amethyst (Faceted Gemstone)

Silicon Dioxide (SiO2) with iron impurities

Polished orbicular granite (likely larvikite or rapakivi-type granite)

Granite; primarily quartz, potassium feldspar, plagioclase, and biotite/hornblende

Green Quartz (Prasiolite or Aventurine)

Silicon Dioxide (SiO2)

Fossiliferous limestone (coral or shell-rich limestone)

Biogenic calcite limestone, mainly calcium carbonate (CaCO₃); exact fossil type is unclear from the image

Dyed and polished agate pebble

Microcrystalline quartz (SiO₂), likely chalcedony/agate with blue dye

Yellow Quartz

Silicon Dioxide (SiO2)

Goldstone (Brown/Gold variety)

Aventurine Glass (SiO2 with Copper inclusions)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Likely iron-rich laterite or limonite/goethite nodule

Hydrated iron oxides, chiefly limonite (FeO(OH)·nH₂O) and/or goethite (FeO(OH))

Black Jasper with Quartz

Silicon Dioxide (SiO2) with impurities

Pearl oyster shell with natural pearls

Molluscan shell, likely Pinctada spp.; pearls are aragonite (CaCO₃)

Tumbled citrine (likely heat-treated amethyst or quartz)

Quartz, SiO₂; yellow coloration from iron impurities or irradiation/heat treatment

Tumbled quartz pebble

Quartz (silicon dioxide, SiO₂)

Polished banded agate (probable)

Microcrystalline quartz, SiO₂ (chalcedony/agate)

Healer's Gold (Iron-Stained Quartz Cluster)

Silicon Dioxide with Iron Oxide Coating (SiO2)

Yellow Quartz (Citrine / Golden Quartz)

Silicon Dioxide (SiO2)

Tumbled amber-brown quartz (probable smoky quartz or carnelian)

Quartz, SiO₂; color may reflect iron impurities or irradiation

Yellow Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine alternative)

Silicon Dioxide (SiO2) with iron impurities

Green Quartz (Prasiolite/Adventurine)

Silicon Dioxide (SiO2) with inclusions

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine-colored Quartz)

Silicon Dioxide (SiO2)