Mineral (Chalcedony Variety)

Polished jasper pebble

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

Tumbled jasper

Microcrystalline quartz (chalcedony), chiefly SiO₂, colored by iron oxides and other impurities

Tumbled jasper (likely brecciated or mahogany jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

Chalcedony (Agate/Chert variety)

Silicon Dioxide (SiO2)

Blue Lace Agate

Chalcedony (SiO2)

Chalcedony (Agate/Carnelian)

Cryptocrystalline Silicon Dioxide (SiO2)

Chalcedony

Silicon Dioxide (SiO2)

Polished jasper pebble

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

Tumbled brown jasper or chalcedony

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

Brecciated jasper

Jasper (microcrystalline quartz, SiO₂), likely iron-oxide-rich breccia

Yellow Chalcedony

Silicon Dioxide (SiO2)

Tumbled agate or chalcedony

Microcrystalline quartz (SiO₂), likely agate/chalcedony with green inclusions

Tumbled blue chalcedony

Chalcedony, microcrystalline quartz (SiO₂)

Weathered agate or chalcedony nodule

Microcrystalline quartz (SiO₂), likely chalcedony/agate

Yellow-orange chalcedony (possibly carnelian)

Microcrystalline quartz, SiO₂; orange coloration commonly from iron oxides

Tumbled amber-colored agate or chalcedony

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

Tumbled gray-blue agate/chalcedony

Microcrystalline quartz (SiO₂), likely banded chalcedony or agate

Tumbled carnelian/chalcedony

Chalcedony (microcrystalline quartz), SiO₂; reddish color from iron oxides

Yellow Agate

Silicon Dioxide (SiO2)

Jasper

Silicon dioxide (SiO2)

Polished brecciated jasper

Microcrystalline quartz (SiO₂), likely iron-oxide-rich jasper

Polished agate slab (likely moss or plume agate)

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

Yellow jasper (likely iron-stained chalcedony)

Microcrystalline quartz, SiO₂, commonly colored by iron oxides/hydroxides

Chalcedony

Chalcedony (SiO2)

White Agate (Chalcedony)

Chalcedony (SiO2)

Lake Superior Agate

SiO2 (Quartz variety chalcedony)

Agate

Chalcedony (SiO2)

Polished jasper pebble (possibly orbicular jasper)

Microcrystalline quartz (SiO₂), likely jasper; exact variety cannot be confirmed visually

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Bloodstone

Chalcedony (Variety Heliotrope), SiO2

Lake Superior Agate

Silicon Dioxide (Chalcedony variety)

Tumbled red-and-cream jasper

Microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides

Tumbled brown agate (possible carnelian or chalcedony)

Microcrystalline quartz, SiO₂; agate is banded chalcedony

Polished orange agate beads

Chalcedony, microcrystalline quartz (SiO₂), commonly sold as agate

Agate (chalcedony), likely a cut nodule

Agate, a banded variety of microcrystalline quartz (SiO₂); associated iron oxides stain the rough outer matrix.

Tumbled jasper

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

Tumbled yellow jasper

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

Agate

Cryptocrystalline quartz, SiO2

Tumbled yellow chalcedony (probable)

Chalcedony, microcrystalline quartz (SiO₂), possibly iron-stained jasper

Sardonyx or Carnelian Agate

Silicon Dioxide (SiO2) with iron impurities

Honey-colored chalcedony (rough agate/chert)

Microcrystalline quartz, SiO₂; likely chalcedony with iron-oxide staining

Tumbled brecciated jasper (likely)

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