Sedimentary (Silicified Fossiliferous Chalcedony)

Petrified Wood

Silicified wood (Quartz, Chalcedony, or Opal)

Petrified Wood

Silicified wood (principally SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Agatized/Silicified Wood)

Silicified Paleoxylon (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO₂)

Petrified Wood

Silicified Wood (SiO2)

Brown chalcedony (likely jasper or petrified wood fragment)

Microcrystalline quartz, SiO₂; brown coloration likely from iron oxides

Tumbled yellow jasper or chalcedony

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

Fossil Coral / Petrifed Coral Agate

Silicified Anthozoa (Agatized Coral)

Agate-bearing chert (likely petrified wood or silica-rich breccia)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide staining and host-rock fragments

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO₂)

Polished petrified wood

Silicified wood (quartz/chalcedony, SiO₂)

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Petrified Wood

Silicified wood (primarily SiO2)

Petrified Wood

Silicified wood (principally SiO2)

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement)

Honey-colored chalcedony (rough agate/chert)

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

Botiroidal Chalcedony or Silicified Fossil Coral

Silicon Dioxide (SiO2) - Chalcedony / Scleractinia (if fossilized)

Chalcedony or chert pebble with iron-oxide staining

Microcrystalline quartz (SiO₂), possibly a weathered chert or flint nodule

Jasper (specifically Owyhee or Picture Jasper variety)

Jasper (Silicon Dioxide, SiO2)

Petrified Wood

Silicified wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified wood / Permineralized wood (SiO2)

Petrified Wood

Petrified Wood (Silicified Wood)

Milky quartz-bearing rock, likely quartzite or silicified limestone

Quartz (SiO₂), possibly in a quartzite or chalcedony-rich matrix

Petrified Wood

Silicified Wood (SiO2 permineralization)

Turritella Fossil

Turritella (Class Gastropoda, Family Turritellidae)

Polished fossiliferous agate

Chalcedony (microcrystalline SiO₂), likely containing fossil coral or stromatoporoid structures

Banded chert or agate

Microcrystalline quartz (chalcedony), SiO₂

Yellow-brown jasper or silicified volcanic rock

Microcrystalline quartz (chalcedony), SiO₂, likely jasper

Petrified Wood

Silicified Wood (SiO2 permineralization)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Fossilized wood / Silicified wood

Silicified oyster fossil

Fossil oyster shell, commonly Ostrea or Crassostrea, replaced or encrusted by chalcedony/quartz

Petrified Wood

Silicified Wood (primarily SiO2)

Polished fossiliferous agate

Chalcedony (microcrystalline SiO₂) containing fossil fragments, likely an agatized limestone or stromatolite

Petrified Wood

Silicified Wood / Xylopal

Petrified Wood

Silicified Wood (primarily SiO2)

Agate with Fossil/Inclusion

Silicon Dioxide (SiO2) with chalcedony and potential fossil inclusion