Mineral_variety_of_chalcedony

Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)

Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)

Red/orange chalcedony (carnelian), possibly dyed or heat-treated

Chalcedony, cryptocrystalline SiO₂ (quartz variety)

Brown chalcedony (likely carnelian/iron-stained quartz)

Microcrystalline quartz, SiO₂; brown coloration from iron oxides/hydroxides

Red Jasper

Red Jasper (variety of Chalcedony, SiO₂)

Jasper (likely brecciated jasper)

Microcrystalline quartz, SiO₂, colored by iron oxides

Black onyx-style bead bracelet

Likely polished black chalcedony (microcrystalline quartz, SiO₂); the beads may also be dyed agate or another black stone.

Polished carnelian agate

Microcrystalline quartz, SiO₂, commonly chalcedony with iron-oxide coloring

Tumbled carnelian (orange chalcedony)

Carnelian, a microcrystalline quartz variety; SiO₂, commonly colored by dispersed iron oxides

Raw carnelian/chalcedony

Microcrystalline quartz (SiO₂), orange chalcedony with iron-oxide coloration

Polished agate (likely moss or plume agate)

Microcrystalline quartz, primarily chalcedony (SiO₂), with possible iron-oxide inclusions

Red jasper (likely brecciated jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides

Tumbled Agate

Silicon Dioxide (SiO2)

Chalcedony-rich agate/jasper

Microcrystalline quartz (SiO₂), likely iron-stained jasper with chalcedony

Brown chalcedony (likely agate/jasper)

Chalcedony, cryptocrystalline SiO₂, with iron-oxide inclusions

Tumbled quartz-rich stone, likely brown agate or jasper

Microcrystalline silica (chalcedony/quartz, SiO₂), possibly iron-stained agate or jasper

Tumbled brown jasper (likely common jasper or chert)

Microcrystalline quartz, SiO₂, chiefly chalcedony/quartz with iron-oxide impurities

Chalcedony (Agate/Carnelian pebbles)

Cryptocrystalline Quartz (SiO2)

Agate

Silicon dioxide (SiO2)

Quartz (Agate/Chalcedony)

Silicon Dioxide (SiO2)

Quartz pebble (Agate / Chalcedony)

Silicon Dioxide (SiO2)

Agate (Carnelian-Blue Agate mix)

Silicon Dioxide (SiO2)

Agate (Chalcedony Variation)

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (SiO2) - variety Chalcedony

Banded Agate (specifically Carnelian Agate)

Silicon dioxide (SiO2) - Chalcedony variety

Tumbled orange-and-white jasper or brecciated chalcedony

Microcrystalline quartz (SiO₂), likely iron-oxide-stained jasper; exact variety cannot be confirmed from the image

Tumbled brown agate

Microcrystalline quartz (SiO₂), variety of chalcedony

Oceanside Agate (Orbicular Agate)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (SiO2)

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

Polished banded agate

Microcrystalline quartz (chalcedony), SiO₂

White Jade / White Chalcedony

Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)

Tumbled brown jasper

Microcrystalline quartz (SiO₂), chiefly chalcedony with iron-oxide pigments

Ocean Jasper

SiO2, highly silicified rhyolite or spherulitic chalcedony

Blue-green agate bead bracelet

Chalcedony (microcrystalline quartz, SiO₂), likely dyed blue-green

Polished agate slab (likely moss or plume agate)

Microcrystalline quartz, SiO₂; chalcedony with possible iron-oxide inclusions

Orange chalcedony (likely carnelian)

Microcrystalline quartz, SiO₂; iron-bearing variety commonly called carnelian

Tumbled brown agate

Chalcedony (microcrystalline quartz), SiO₂, with iron-oxide coloration

Polished agate or jasper pebble

Microcrystalline quartz (chalcedony), SiO₂, possibly iron-oxide-bearing

Red jasper

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

Agate

SiO2