Mineral (Specifically A Variety Of Chalcedony, Which Is A Cryptocrystalline Quartz)

Flint

Microcrystalline quartz (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Agate (Plume/Moss variety)

Cryptocrystalline Quartz (SiO2) with iron/manganese inclusions

Chert (or Flint)

SiO2 (predominantly microcrystalline quartz)

Polished banded agate, likely moss or dendritic agate

Microcrystalline quartz (chalcedony), SiO₂, with iron/manganese inclusions

Chert (Tripolitic Chert / Flint Nodules)

Microcrystalline Quartz (SiO2)

Tumbled carnelian (likely)

Cryptocrystalline quartz, SiO₂; orange chalcedony colored mainly by iron oxides

Blue Lace Agate

Chalcedony (SiO2) with trace minerals

Chert (with Quartz veins)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Chert Nodule

Microcrystalline Quartz (SiO2)

Tumbled pink banded agate

Chalcedony (microcrystalline quartz, SiO₂), an agate variety

Tumbled agate or chalcedony

Microcrystalline quartz (SiO₂), likely gray/brown chalcedony with subtle agate banding

Agate

Chalcedony (SiO2)

Polished/tumbled agate (likely carnelian or iron-stained chalcedony)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide inclusions

Orange chalcedony (carnelian)

Microcrystalline quartz, SiO₂; orange variety of chalcedony

Tumbled pink chalcedony (likely rose quartz or pink agate)

Chalcedony, microcrystalline quartz (SiO₂); exact variety is uncertain from the image

Tumbled brown agate

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

Tumbled carnelian/chalcedony

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony

Banded Agate (specifically Lake Superior Agate style)

Agate (Cryptocrystalline Quartz), SiO2

Polished banded jasper

Jasper, microcrystalline quartz (SiO₂) with iron-oxide inclusions

Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Banded Black Onyx (Chalcedony)

Silicon Dioxide (SiO₂)

Jasper (River pebble)

Jasper / Silicon Dioxide (SiO2)

Honey-colored chalcedony (likely rough agate/jasper)

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony

Orbicular Jasper

Silicon Dioxide (SiO2), variety of Chalcedony

Botryoidal Chalcedony with Calcite

Chalcedony (SiO2 with accessory minerals, likely CaCO3)

Chalcedony (Tumbled Pebble)

Silicon Dioxide (SiO2)

Dyed and polished crackle agate bead

Agate, microcrystalline quartz (SiO₂), commonly artificially crackled and dyed

Tumbled agate/chalcedony pebble

Microcrystalline quartz (SiO₂), likely agate or jasper variety

Polished jasper or iron-stained chert

Microcrystalline quartz (SiO₂), commonly chalcedony with iron-oxide staining

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony variety

Polished red jasper beads

Jasper, microcrystalline quartz (SiO₂), colored mainly by iron oxides

Tumbled jasper, likely picture or brecciated jasper

Microcrystalline quartz (SiO₂) with iron-oxide and other mineral impurities

Polished agate (likely carnelian/mossy chalcedony)

Chalcedony, microcrystalline quartz (SiO₂), with iron-oxide banding and possible inclusions

Chalcedony Geode Fragment

Silicon Dioxide (SiO2)

Tumbled blue chalcedony (likely dyed)

Cryptocrystalline quartz, SiO₂; chalcedony variety

Banded Agate (Lake Superior Agate type)

Agate (Cryptocrystalline Variety of Quartz, SiO2)

Tumbled jasper pebble

Jasper, microcrystalline quartz (SiO₂) with iron-oxide impurities

Botryoidal chalcedony (likely quartz with iron staining)

Chalcedony, cryptocrystalline SiO₂; possible quartz druse and limonite/goethite inclusions

Raw orange chalcedony (carnelian-like)

Chalcedony, microcrystalline quartz (SiO₂), colored by iron oxides

Polished jasper, likely orbicular or brecciated jasper

Jasper: microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides and other inclusions

Polished carnelian

Carnelian, a translucent variety of chalcedony (microcrystalline quartz, SiO₂), colored mainly by iron oxides