Mineral, Variety Of Chalcedony (Microcrystalline Quartz)

Yellow Jasper

Silicon Dioxide (SiO2)

Tumbled blue-green chalcedony (likely dyed agate or chrysoprase)

Microcrystalline quartz, SiO₂; chalcedony/agate variety

Jasper (Milky/Cream Variety)

Silicon Dioxide (SiO2) - variety of Chalcedony

Tumbled brown jasper

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

Blue Lace Agate

Silicon Dioxide (Chalcedony variety), SiO2

Tumbled chalcedony (likely yellow/brown jasper or agate)

Microcrystalline quartz, SiO₂ (chalcedony; variety uncertain)

Polished agate geode slice

Agate, a banded variety of microcrystalline quartz (SiO₂); likely quartz/chalcedony lining a geode

Tumbled brecciated jasper

Jasper, a microcrystalline quartz variety (SiO₂), with iron-oxide-rich matrix or veining

Tumbled translucent pebble, likely quartz or pale chalcedony

Quartz (SiO₂), possibly microcrystalline chalcedony

Polished orbicular jasper (likely ocean jasper or rhyolitic jasper)

Microcrystalline quartz (SiO₂) with iron-oxide and altered volcanic inclusions

Tumbled amber-colored chalcedony or jasper

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

Tumbled agate or chalcedony pebble

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

Tumbled jasper (likely mookaite or brown/orange jasper)

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

Tumbled carnelian and related stones

Carnelian: orange-red chalcedony, microcrystalline SiO₂; the dark central piece may be hematite- or jasper-rich material

Carnelian

Quartz (chalcedony variety), SiO2

Tumbled chalcedony (likely gray/brown agate)

Microcrystalline quartz, SiO₂ (chalcedony; possible agate variety)

Polished carnelian agate

Chalcedony (microcrystalline quartz), SiO₂, iron-oxide colored

Banded agate (likely jasper/chalcedony nodule)

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

Iron-stained jasper (likely orbicular/brecciated jasper)

Microcrystalline quartz, SiO₂, colored by iron oxides/hydroxides

Yellow jasper (likely iron-stained chalcedony)

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

Quartz (Agate/Chalcedony)

Silicon Dioxide (SiO2)

Pink Dyed Agate (Banded Chalcedony)

Silicon dioxide (SiO2) - variety Chalcedony

Tumbled carnelian (orange chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂)

Quartz (or Chalcedony) Specimen

Silicon Dioxide (SiO2)

Tumbled brown chalcedony or jasper

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

Chalcedony

Silicon Dioxide (SiO2)

Likely polished agate or chalcedony pebble

Chalcedony, microcrystalline quartz (SiO₂); exact variety cannot be confirmed from the image

Agate nodule (cross-section)

Microcrystalline quartz (SiO₂), a banded variety of chalcedony

Mixed polished gemstones and minerals

Likely agate/chalcedony (SiO₂), quartz, jasper, and possibly aventurine or obsidian; exact identification requires individual testing.

Polished agate (likely moss or plume agate)

Microcrystalline quartz (SiO₂), chalcedony variety; exact variety is uncertain from the photo

Polished banded agate pebble

Agate, a variety of microcrystalline quartz (SiO₂; chalcedony)

Flint / Chert Pebble

Microcrystalline quartz (SiO2)

Ocean Jasper

SiO2 (Silicon Dioxide) - Chalcedony variety

Red jasper

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

Yellow Chalcedony (Agate/Carnelian)

Silicon Dioxide (SiO2)

Agate Geode Node

Cryptocrystalline Quartz (SiO2)

Polished jasper pebble

Jasper, an opaque microcrystalline variety of quartz (SiO₂), often chalcedony with iron-oxide inclusions

Polished orange chalcedony or carnelian

Microcrystalline quartz (SiO₂), commonly called carnelian when orange-red

Polished brecciated jasper

Jasper (microcrystalline quartz, SiO₂), brecciated variety

Tumbled brown chalcedony or agate

Microcrystalline quartz, SiO₂ (likely chalcedony; banding is not visible)

Polished carnelian/chalcedony agate

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

Tumbled honey-brown chalcedony (likely common quartz)

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony or low-grade agate