Mineral, Variety Of Chalcedony (Microcrystalline Quartz)

Tumbled jasper, likely red jasper

Microcrystalline quartz (SiO₂), chalcedony variety with iron-oxide impurities

Red jasper

Microcrystalline quartz (SiO₂), colored mainly by iron oxides

Red jasper (probable)

Microcrystalline quartz/chalcedony (SiO₂) colored by iron oxides

Polished reddish-brown gemstone, likely carnelian

Carnelian: chalcedony, microcrystalline quartz (SiO₂), colored mainly by iron oxides

Red Chalcedony (likely dyed)

Chalcedony (a variety of Quartz), SiO2

Zebra Jasper

Jasper (variety of Quartz/Chalcedony), SiO2

Tumbled jasper (likely picture/brecciated jasper)

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

Jasper (likely brecciated jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored by iron oxides

Polished jasper pebble

Microcrystalline quartz (chalcedony), usually with iron-oxide impurities

Tumbled banded agate

Microcrystalline quartz (chalcedony), SiO₂, with layered impurities

Jasper with Quartz Veins

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Agate (specifically a Blue Agate Geode Slice)

Chalcedony (cryptocrystalline variety of Quartz); SiO2

Jasper

Jasper (Silicon Dioxide, SiO2)

Tumbled brown agate/chalcedony (probable)

Microcrystalline quartz, SiO₂; likely iron-stained agate or jasper

Polished banded jasper

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

Tumbled agate or chalcedony

Microcrystalline quartz (SiO₂), likely brown/orange chalcedony or agate

Polished brecciated jasper

Microcrystalline quartz (SiO₂), commonly with iron-oxide and clay-mineral inclusions

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Chert (Chalcedony/Quartz)

Microcrystalline Silicon Dioxide (SiO2)

Tumbled yellow chalcedony (likely yellow jasper)

Microcrystalline quartz, SiO₂; chalcedony/jasper variety

Tumbled banded agate

Agate, microcrystalline chalcedony (SiO₂)

Tumbled yellow chalcedony (likely honey agate or yellow quartz)

Microcrystalline quartz, SiO₂; coloration likely from iron oxides or included minerals

Tumbled orange-and-white chalcedony

Chalcedony, microcrystalline quartz (SiO₂), likely orange carnelian/white agate variety

Carnelian (Tumbled Quartz)

Silicon Dioxide (SiO2) - Chalcedony variety

Carnelian

Silicon Dioxide (Chalcedony variety), SiO2

Tumbled carnelian/chalcedony

Orange chalcedony (microcrystalline quartz), SiO₂; possibly iron-stained agate

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides

Chert

Microcrystalline quartz (SiO2)

Tumbled orange chalcedony or quartzite

Microcrystalline quartz (SiO₂), possibly iron-stained chalcedony; exact identification requires testing

Polished banded agate

Banded chalcedony, microcrystalline quartz (SiO₂)

Tumbled jasper and agate

Microcrystalline quartz (SiO₂), likely jasper/chalcedony; exact varieties cannot be confirmed from the image

Blue Lace Agate (often dyed)

Silicon dioxide (SiO2) - variety of chalcedony

Likely tumbled quartz/chalcedony

Quartz (SiO₂), possibly milky quartz or pale chalcedony

Tumbled brown chalcedony (likely jasper or agate)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide staining

Tumbled red jasper

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

Tumbled red jasper

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

Polished brecciated jasper (likely Apache tear–type iron-rich jasper)

Jasper, microcrystalline quartz (SiO₂), colored by hematite/goethite and other iron oxides

Tumbled yellow-brown agate

Agate, a banded variety of microcrystalline quartz (SiO₂)

Agate in Matrix

Silicon Dioxide (SiO2) within host rock

Polished brecciated jasper

Jasper, microcrystalline quartz (SiO₂), with iron-oxide and silica vein infill

Carnelian (Banded Agate)

Carnelian Chalcedony (SiO2)

Carnelian / Agate

Silicon Dioxide (SiO2) - Chalcedony variety