Mineral (Chalcedony Variety)

Polished banded agate (likely carnelian agate)

Microcrystalline quartz, SiO₂ (chalcedony); iron-oxide coloring

Green tumbled agate (likely green chalcedony)

Chalcedony, microcrystalline quartz (SiO₂); exact identification is uncertain from the photo

Tumbled chalcedony (likely brown agate)

Chalcedony, microcrystalline quartz (SiO₂); possibly agate

Polished pink-orange chalcedony (likely carnelian)

Microcrystalline quartz, SiO₂; carnelian is orange-red chalcedony

Jasper

Microcrystalline Quartz (SiO2)

Carnelian Agate

Silicon Dioxide (SiO2)

Chalcedony

Silicon Dioxide (SiO2)

Polished banded jasper (likely red jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored by iron oxides; exact variety uncertain

Tumbled brown jasper

Microcrystalline quartz (chalcedony), SiO₂; likely jasper

Polished banded agate

Microcrystalline quartz (SiO₂), chiefly chalcedony

Agate

Chalcedony (SiO2)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Tumbled/rounded agate (likely mossy or brecciated chalcedony)

Microcrystalline quartz, SiO₂ (chalcedony/agate)

Agate (Puddingstone style)

Silicon Dioxide (SiO2) with impurities

Tumbled chalcedony/agate (likely iron-stained quartz)

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

Red Jasper

Silicon Dioxide (SiO2) - variety Jasper

Polished brecciated jasper (likely)

Microcrystalline quartz, SiO₂, with iron-oxide-rich brown fragments and pale silica

Tumbled jasper or chert

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

Tumbled Black Stone

Unknown, possibly Obsidian, Onyx, or Tourmaline

Polished orbicular jasper (likely ocean jasper)

Silica-rich microcrystalline quartz/chalcedony, SiO₂; precise variety uncertain from the photo

Tumbled brown chalcedony (likely carnelian/agatesque material)

Microcrystalline quartz, SiO₂; chalcedony variety

Red jasper (likely tumbled)

Microcrystalline quartz, chiefly SiO₂, colored red by iron oxides

Polished agate/geode slab

Banded chalcedony (microcrystalline quartz, SiO₂), likely with quartz crystals

Tumbled blue-green stone, likely dyed agate

Agate (microcrystalline quartz, SiO₂); blue coloration may be artificial

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Agate Slab

Chalcedony (SiO2)

Tumbled agate or chalcedony

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/agate

Polished carnelian/chalcedony

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony

Tumbled yellow jasper or chalcedony

Microcrystalline quartz, SiO₂; likely iron-oxide-bearing jasper/chalcedony

Tumbled amber-colored chalcedony or jasper

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

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Tumbled chalcedony (likely moss or gray agate)

Microcrystalline quartz, SiO₂; chalcedony/agate variety

Polished agate (likely chalcedony)

Microcrystalline quartz, SiO₂; agate is banded chalcedony

Jasper / Chert (river tumbled)

Microcrystalline Quartz (SiO2)

Polished carnelian jasper / brecciated jasper

Microcrystalline quartz (SiO₂), chalcedony with iron-oxide pigments and opaque jasper fragments

Geode (Unopened)

Quartz/Chalcedony concretion

Tumbled agate/chalcedony

Microcrystalline quartz (SiO₂), likely banded chalcedony or agate

Tumbled agate and chalcedony specimens

Microcrystalline quartz (SiO₂), chiefly chalcedony/agate

Tumbled orange chalcedony (likely carnelian)

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

Chalcedony

Chalcedony (a microcrystalline variety of Quartz, SiO2)

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image

Yellow Chalcedony

Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)