All rocks & minerals

Possible ironstone concretion or weathered sulfide-bearing rock

Indeterminate from the photograph; possibly goethite/limonite-rich ironstone

Pyrite (iron pyrite)

Pyrite, FeS₂; cubic iron sulfide

Pyrite (fool’s gold)

Pyrite, FeS₂

Polished purple gemstone bead, possibly amethyst

Likely amethyst, purple quartz (SiO₂); identification is uncertain from the image

Tumbled amethyst

Amethyst, purple variety of quartz (SiO₂)

Tumbled amethyst

Quartz, SiO₂; purple color from trace iron and natural irradiation

Tumbled amethyst

Quartz, SiO₂; purple coloration from trace iron and irradiation

Tumbled amethyst

Quartz (SiO₂), purple variety known as amethyst

Tumbled purple gemstone, likely amethyst

Quartz (SiO₂), purple variety colored by trace iron and irradiation

Likely rough amethyst

Quartz, SiO₂; purple variety colored mainly by iron impurities

Tumbled moonstone (likely)

Feldspar, likely orthoclase or plagioclase; composition varies, approximately (K,Na,Ca)(Al,Si)₄O₈

Rough blue-gray sapphire (possible corundum)

Corundum, Al₂O₃; sapphire is gem-quality corundum

Tumbled red jasper

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

Likely rose quartz-bearing pegmatite

Quartz (SiO₂), possibly with feldspar and mica; exact identification is uncertain from the photo

Likely mica-rich schist

Mica schist, likely containing quartz, feldspar, and biotite or muscovite

Black stone-bead bracelet, likely black onyx or agate

Probably chalcedony, microcrystalline quartz (SiO₂); the photo alone cannot confirm the bead material

Weathered granite (likely)

Granite; a coarse-grained rock composed mainly of quartz, feldspar, and mica

Weathered, garnet-bearing schist (tentative identification)

Mica schist, likely quartz–feldspar–mica schist; exact minerals cannot be confirmed from the photograph

Weathered biotite-rich granite gneiss

Foliated granitoid gneiss, chiefly quartz and feldspars with biotite mica

Polished eye agate

Quartz (SiO₂), commonly chalcedony with concentric fortification bands

Orange agate (chalcedony), possibly carnelian

Microcrystalline quartz, SiO₂; agate is banded chalcedony, while carnelian is orange chalcedony

Orange carnelian (likely)

Carnelian, orange chalcedony; microcrystalline quartz (SiO₂)

Polished banded agate

Agate, a banded variety of chalcedony (microcrystalline SiO₂)

Tumbled greenstone (likely serpentine-rich)

Serpentinite or chlorite/epidote-rich greenstone; exact identification requires testing

Weathered quartz-rich pebble

Likely massive quartz (SiO₂), possibly milky quartz with iron-oxide staining

Tumbled carnelian (likely)

Cryptocrystalline silica, chiefly chalcedony (SiO₂), colored by iron oxides

Rounded banded pebble (likely sandstone or quartzite)

Unidentified silica-rich rock; exact lithology cannot be determined from the image

Green faceted or cabochon gemstone (possibly glass or synthetic)

Undetermined; possibilities include green beryl (Be₃Al₂Si₆O₁₈), quartz (SiO₂), or synthetic glass

Banded quartzite pebble

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

Polished jasper pebble, likely red/orange jasper

Microcrystalline quartz (SiO₂), opaque variety commonly colored by iron oxides

Polished brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide staining

Tumbled banded agate (likely carnelian agate)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide coloring

Tumbled orange calcite

Calcite (CaCO₃)

Granite pebble

Granite, chiefly quartz, potassium feldspar, and plagioclase, with dark biotite or amphibole

Greenstone (likely serpentine-rich rock)

Serpentinite, composed mainly of serpentine-group minerals

Iron-stained milky quartz

Quartz (SiO₂), with reddish-brown iron-oxide staining

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂); likely iron-oxide colored

Weathered granite pebble

Granite, a coarse-grained felsic intrusive igneous rock

Porphyritic volcanic rock, possibly porphyritic andesite

Likely andesite porphyry; exact identification requires close examination

Rough orange opal

Opal, hydrated amorphous silica (SiO₂·nH₂O)

Pale green rough mineral fragment, possibly amazonite

Unconfirmed; possibly amazonite, a green variety of microcline feldspar (KAlSi₃O₈)

Tumbled unakite

Unakite: epidote, pink potassium feldspar (orthoclase), and commonly quartz