Antropogenic (Man Made Glass Byproduct)

Quartz

Silicon Dioxide (SiO₂)

Quartz-rich rock, possibly milky quartz or quartzite

Quartz (SiO₂), potentially quartzite if the grains are fused

Tumbled amethyst

Quartz, purple variety; silicon dioxide (SiO₂), colored mainly by iron impurities and irradiation

Quartz

Quartz (SiO₂)

Quartz (River Pebble)

Quartz (SiO₂ - Silicon Dioxide)

Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz

Quartz (SiO2)

Smoky Quartz

SiO2 (Silicon Dioxide)

Likely tumbled amber or orange chalcedony

Uncertain from image; possibly amber (fossilized resin, chiefly C10H16O) or carnelian (microcrystalline quartz, SiO₂)

Turquoise cabochon jewelry

Turquoise, hydrated copper–aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Weathered quartz-rich pebble (probable quartzite or quartz vein fragment)

Quartzite, predominantly silicon dioxide (SiO₂); exact identification is uncertain from the photograph

Jasper (yellow/cream variety)

SiO₂ (Cryptocrystalline Quartz)

Clear quartz crystal sphere

Quartz (silicon dioxide, SiO₂)

Lazulite

Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2

Banded malachite cabochon

Malachite, Cu₂CO₃(OH)₂; the dark bands may be manganese-oxide or other sulfide-rich matrix, and could also indicate a composite or treated specimen

Quartzite

Quartzite (primarily SiO2)

Scoria

Scoria (a vesicular basalt or andesite)

Raw milky quartz

Quartz (silicon dioxide, SiO₂)

Orange Quartz (Citrine Quartz)

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartzite Pebble

Quartzite (SiO2)

Quartz

Quartz (SiO2 - Silicon Dioxide)

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Blue Sapphire

Corundum (Al2O3)

Chert or flint fragment

Microcrystalline quartz (SiO₂), likely silicified rock

Sandstone (likely a river or beach pebble)

Sandstone (a clastic sedimentary rock)

Quartz

Quartz (SiO₂)

Polished blue chalcedony (likely blue quartz/chalcedony)

Microcrystalline quartz, SiO₂; blue color commonly from inclusions or coloration

Tumbled quartz-rich pebble, possibly quartzite

Quartzite (mostly SiO₂), or quartz-bearing chert; exact identification requires testing

Quartzite

Quartzite (primarily SiO2)

Sandstone

Arenite

Quartz

Quartz (SiO₂)

Likely weathered quartz-bearing rock fragment

Indeterminate; appears to contain quartz (SiO₂) with iron-oxide staining, possibly from quartzite, granite, or pegmatite

Quartzite

Quartzite (primarily SiO2)

Quartz

Quartz (SiO2 - Silicon Dioxide)

Tumbled brown chalcedony (likely jasper or agate)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide staining

Sandstone (Pebble)

Arenite

Quartzite River Rock

Quartzite (primarily SiO2)

Likely weathered quartz-rich rock, possibly smoky quartz or chert

Quartz (SiO₂), though exact identification is uncertain from the photograph

Quartz

Quartz (Silicon Dioxide - SiO2)

Tumbled pale stone, likely milky quartz or calcite

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Quartz crystal point (likely smoky or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled carnelian

Carnelian, orange-red variety of cryptocrystalline chalcedony (SiO₂)